Merge changes from release branch into trunk.

doc/ZEO/ClientStorage.txt

@@ -23,7 +23,9 @@ ClientStorage
       - a sequence of the previous two
 
     If a sequence of addresses is specified, the client will use the
-    first server from the list that it can connect to.
+    first server from the list that it can connect to, subject to the
+    constraints imposed by the optional read_only and
+    read_only_fallback keyword arguments.
 
     The ClientStorage constructor provides a number of additional
     options (arguments). The full list of arguments is:
@@ -36,7 +38,7 @@ ClientStorage
       default name for both the server and client is '1'.
 
     cache_size -- The number of bytes to allow for the client cache.
-      The default is 20,000,000.  A large cache can significantly
+      The default is 20MB.  A large cache can significantly
       increase the performance of a ZEO system.  For applications that
       have a large database, the default size may be too small.
 
@@ -93,3 +95,8 @@ ClientStorage
 
       Each storage served by a ZEO server can be configured as either
       read-write or read-only.
+
+    read_only_fallback -- A flag indicating whether a read-only
+      remote storage should be acceptable as a fallback when no
+      writable storages are available.  Defaults to false.  At most
+      one of read_only and read_only_fallback should be true.

doc/ZEO/NonZopeREADME.txt

@@ -20,7 +20,7 @@ Zope Enterprize Objects
       python test.py -v
 
     Run the script with the -h option for a full list of options.  The
-    ZEO 2.0a1 release contains 87 unit tests on Unix.
+    ZEO 2.0b2 release contains 122 unit tests on Unix.
 
   Starting (and configuring) the ZEO Server
 
@@ -75,6 +75,6 @@ Zope Enterprize Objects
 
   Dependencies on other modules
 
-    ZEO depends on other modules that are distributed with
-    StandaloneZODB and with Zope.  You can download StandaloneZODB
-    from http://www.zope.org/Products/StandaloneZODB.
+    ZEO depends on other modules that are distributed with ZODB3 and
+    with Zope.  You can download ZODB3 from
+    http://www.zope.org/Products/StandaloneZODB.

doc/ZEO/ZopeREADME.txt

-Zope Enterprise Objects
+Zope Enterprise Objects (ZEO)
 
   Installation
 
@@ -19,7 +19,7 @@ Zope Enterprise Objects
       python test.py -v
 
     Run the script with the -h option for a full list of options.  The
-    ZEO 2.0a1 release contains 87 unit tests on Unix.
+    ZEO 2.0b2 release contains 122 unit tests on Unix.
 
   Starting (and configuring) the ZEO Server
 
@@ -93,4 +93,4 @@ Zope Enterprise Objects
     once with the environment variable FORCE_PRODUCT_LOAD set.
 
     The interaction between ZEO and Zope product installation is
-    unfortunate.  In the future, this interaction will be removed by 
+    unfortunate.

doc/guide/TODO

-Update text to use BTrees, not BTree
 Write section on __setstate__
-Connection.sync seems to work now; note this
 Continue working on it
 Suppress the full GFDL text in the PDF/PS versions
 

doc/guide/links.tex

@@ -17,6 +17,14 @@ how it's actually implemented.  A definitive reference, and highly recommended.
 \\
 \url{http://www.python.org/workshops/2000-01/proceedings/papers/fulton/zodb3.html}
 
+Persistent Programing with ZODB, by Jeremy Hylton and Barry Warsaw:
+\\
+Slides for a tutorial presented at the 10th Python conference.  Covers
+much of the same ground as this guide, with more details in some areas
+and less in others.
+\\
+\url{http://www.zope.org/Members/bwarsaw/ipc10-slides}
+
 Download link for ZEO: \\
 \url{http://www.zope.org/Products/ZEO/}
 

doc/guide/modules.tex

@@ -2,13 +2,12 @@
 % Related Modules
 %    PersistentMapping
 %    PersistentList
-%    BTree
-%    Catalog
+%    BTrees
 
 \section{Related Modules}
 
 The ZODB package includes a number of related modules that provide
-useful data types such as BTrees or full-text indexes.
+useful data types such as BTrees.
 
 \subsection{\module{ZODB.PersistentMapping}}
 
@@ -40,51 +39,92 @@ value for \var{initlist}, a regular Python list is used.
 Python lists do.
 
 
-\subsection{B-tree Modules}
-
-%here's one: how does one implement searching? i would have expected the
-%btree objects to have ``find key nearest to this'' and ``next'' methods,
-%(like bsddb's set_location)...
-%
-%  -- erno
+\subsection{BTrees Package}
 
 When programming with the ZODB, Python dictionaries aren't always what
 you need.  The most important case is where you want to store a very
 large mapping.  When a Python dictionary is accessed in a ZODB, the
 whole dictionary has to be unpickled and brought into memory.  If
 you're storing something very large, such as a 100,000-entry user
-database, unpickling such a large object will be slow.  B-trees are a
+database, unpickling such a large object will be slow.  BTrees are a
 balanced tree data structure that behave like a mapping but distribute
-keys throughout a number of tree nodes.  Nodes are then only unpickled
-and brought into memory as they're accessed, so the entire tree
-doesn't have to occupy memory (unless you really are touching every
-single key).
-
-There are four different BTree modules provided.  One of them, the
-\module{BTree} module, provides the most general data type; the keys
-and values in the B-tree can be any Python object.  Some specialized B-tree
-modules require that the keys, and perhaps even the values, to be of a
-certain type, and provide faster performance because of this limitation.
-
-\begin{itemize}
-\item[ \module{IOBTree} ] requires the keys to be integers.
-The module name reminds you of this; the \module{IOBTree} module
-maps Integers to Objects.
-
-\item[ \module{OIBTree} ] requires the values to be integers,
-mapping Objects to Integers.
-
-\item[ \module{IIBTree} ] is strictest, requiring that both keys and values must be integers.
-
-\end{itemize}
-
-To use a B-tree, simply import the desired module and call the
-constructor, always named \function{BTree()}, to get a B-tree
-instance, and then use it like any other mapping:
+keys throughout a number of tree nodes.  The nodes are stored in
+sorted order.  Nodes are then only unpickled and brought into memory
+as they're accessed, so the entire tree doesn't have to occupy memory
+(unless you really are touching every single key).
+
+The BTrees package provides a large collection of related data
+structures.  There are variants of the data structures specialized to
+handle integer values, which are faster and use less memory.  There
+are four modules that handle the different variants.  The first two
+letters of the module name specify the types of the keys and values in
+mappings -- O for any object and I for integer.  The
+\module{BTrees.IOBTree} module provides a mapping that accepts integer
+keys and arbitrary objects as values.
+
+The four data structures provide by each module are a btree, a bucket,
+a tree set, and a set.  The btree and bucket types are mappings and
+support all the usual mapping methods, e.g. \function{update()} and
+\function{keys()}.  The tree set and set types are similar to mappings
+but they have no values; they support the methods that make sense for
+a mapping with no keys, e.g. \function{keys()} but not
+\function{items()}.  The bucket and set types are the individual
+building blocks for btrees and tree sets, respectively.  A bucket or
+set can be used when you are sure that it will have few elements.  If
+the data structure will grow large, you should use a btree or tree
+set.
+
+The four modules are named \module{OOBTree}, \module{IOBTree},
+\module{OIBTree}, and \module{IIBTree}.  The two letter prefixes are
+repeated in the data types names.  The \module{BTrees.OOBTree} module
+defines the following types: \class{OOBTree}, \class{OOBucket},
+\class{OOSet}, and \class{OOTreeSet}.
+
+The \function{keys()}, \function{values()}, and \function{items()}
+methods do not materialize a list with all of the data.  Instead, they
+return lazy sequences that fetch data from the BTree as needed.  They
+also support optional arguments to specify the minium and maximum
+values to return.
+
+A BTree object supports all the methods you would expect of a mapping
+with a few extensions that exploit the fact that the keys are sorted.
+The example below demonstrates how some of the methods work.  The
+extra methods re \function{minKey()} and \function{maxKey()}, which
+find the minimum and maximum key value subject to an optional bound
+argument, and \function{byValue()}, which returns value, key pairs
+in reversed sorted order subject to an optional minimum bound argument.
 
 \begin{verbatim}
-import IIBTree
-iimap = IIBTree.BTree()
-iimap[1972] = 27
+>>> from BTrees.OOBTree import OOBTree
+>>> t = OOBTree()
+>>> t.update({ 1: "red", 2: "green", 3: "blue", 4: "spades" })
+>>> len(t)
+4
+>>> t[2]
+'green'
+>>> t.keys()
+<OOBTreeItems object at 0x40269098>
+>>> [k for k in t.keys()] # use a listcomp to get a printable sequence
+[1, 2, 3, 4]
+>>> [k for k in t.values()]
+['red', 'green', 'blue', 'spades']
+>>> [k for k in t.values(1, 2)]
+['red', 'green']
+>>> [k for k in t.values(2)]
+['green', 'blue', 'spades']
+>>> t.byValue("glue") # all values > "glue"
+[('spades', 4), ('red', 1), ('green', 2)]
+>>> t.minKey(1.5)
+2
 \end{verbatim}
 
+Each of the modules also defines some functions that operate on
+BTrees -- \function{difference()}, \function{union()}, and
+\function{difference()}.  The \function{difference()} function returns
+a bucket, while the other two methods return a set.
+If the keys are integers, then the module also defines
+\function{multiunion()}.  If the values are integers, then the module
+also defines \function{weightedIntersection()} and
+\function{weighterUnion()}.  The function doc strings describe each
+function briefly.
+

doc/guide/prog-zodb.tex

@@ -23,59 +23,21 @@ difficulties you encounter.
 
 \subsubsection{Requirements}
 
-You'll need Python, of course; version 1.5.2 works with some fixes,
-and it also works with Python 2.0, which is what I primarily use.
-
-The code is packaged using Distutils, the new distribution tools for
-Python introduced in Python 2.0.  If you're using 1.5.2, first you'll
-have to get the latest Distutils release from the Distutils SIG page
-at \url{http://www.python.org/sigs/distutils-sig/download.html} and
-install it.  This is simply a matter of untarring or unzipping the
+You will need Python 2.1 or higher.  The code is packaged using
+Distutils.  So it is simply a matter of untarring or unzipping the
 release package, and then running \code{python setup.py install}.
 
-If you're using 1.5.2 and have installed previous versions of the
-Distutils, be sure to get the very latest version, since developing
-the ZODB distribution turned up some bugs along the way.  If you
-encounter problems compiling \file{ZODB/TimeStamp.c} or your compiler reports
-an error like ``Can't create build/temp.linux2/ExtensionClass.o: No
-such file or directory'', you need an updated version.  Old versions of
-Distutils have two bugs which affect the setup scripts.  First, for a
-long time the \code{define_macros} keyword in setup.py files didn't work due
-to a Distutils bug, so I hacked TimeStamp.c in earlier releases.  The
-Distutils have since been fixed, and the hack became unnecessary, so I
-removed it.  Second, the code that creates directories tries to be
-smart and caches them to save time by not trying to create a directory
-twice, but this code was broken in old versions.
-
 You'll need a C compiler to build the packages, because there are
 various C extension modules.  At the moment no one is making Windows
-binaries available, so you'll need a Windows development environment to use the 
+binaries available, so you'll need a Windows development environment
+to build ZODB.
 
 \subsubsection{Installing the Packages}
 
 Download the ZODB tarball containing all the packages for both ZODB
-and ZEO from \url{http://www.amk.ca/files/zodb/}.
-
-To build the packages, you must go into the individual directories and
-build and install them one by one.  They should be built and installed
-in this order:
- 
-\begin{enumerate}
-  \item \code{zodb-basic}
-  \item ExtensionClass
-  \item ZODB
-  \item \code{BTree} and \code{BTrees}
-  \item ZEO
-\end{enumerate}
-
-In particular, you must install ExtensionClass before building the
-ZODB package; otherwise, the compilation in the ZODB package will die
-complaining that it can't find ExtensionClass.h.  You can manually
-hack the \#include path to make it work without installing
-ExtensionClass first, but that's a bit hackish.
-
-If you encounter any problems, please let me know at
-\email{akuchlin@mems-exchange.org}.
+and ZEO from \url{http://www.zope.org/Products/StandaloneZODB}.  See
+the \file{README.txt} file in the top level of the release directory
+for details on building, testing, and installing.
 
 \subsection{How ZODB Works}
 
@@ -113,10 +75,16 @@ state.
 
 \item[Consistency] means that the data cannot be placed into a
 logically invalid state; sanity checks can be written and enforced.
-Usually this is done by defining a database schema, and requiring the
-data always matches the schema.  For example, this might enforce that
-the \code{order_number} attribute is always an integer, and not a
-string, tuple, or other object.
+Usually this is done by defining a database schema, and requiring
+the data always matches the schema.  There are two typical
+approaches to consistency.  One is to enforce rules about the types
+of objects and attribute; for example, enforce that the
+\code{order_number} attribute is always an integer, and not a
+string, tuple, or other object.  Another is to guarantee consistency
+across data structures; for example, that any object with an
+\code{order_number} attribute must also appear in the
+\code{orders_table} object.  In general, atomicity and isolation make
+it possible for applications to provide consistency.
 
 \item[Isolation] means that two programs or threads running in two
  different transactions cannot see each other's changes until they
@@ -144,7 +112,7 @@ implement the \class{Storage} interface.
  storing and retrieving objects from some form of long-term storage.
  A few different types of Storage have been written, such as
  \class{FileStorage}, which uses regular disk files, and
- \class{BerkeleyStorage}, which uses Sleepycat Software's BerkeleyDB
+ \class{bsddb3Storage}, which uses Sleepycat Software's BerkeleyDB
  database.  You could write a new Storage that stored objects in a
  relational database or Metakit file, for example, if that would
  better suit your application.  Two example storages,
@@ -156,7 +124,7 @@ implement the \class{Storage} interface.
  created per process.
 
  \item Finally, the \class{Connection} class caches objects, and moves
- them into and out of object storage.  A multi-threaded program can
+ them into and out of object storage.  A multi-threaded program should
  open a separate \class{Connection} instance for each thread.
  Different threads can then modify objects and commit their
  modifications independently.
@@ -199,6 +167,10 @@ needed for the following \code{from...import} statement to work
 correctly, since the ZODB code does some magical tricks with
 importing.
 
+The \class{Persistent} base class is an \module{ExtensionClass}
+class.  As a result, it not compatible with new-style classes or types
+in Python 2.2 and up.
+
 For simplicity, in the examples the \class{User} class will
 simply be used as a holder for a bunch of attributes.  Normally the
 class would define various methods that add functionality, but that
@@ -304,11 +276,6 @@ defined on ExtensionClasses.  The most important ones are the
 arithmetic operations: \method{__radd__}, \method{__rsub__}, and so
 forth.
 
-\item Python's built-in \function{isinstance()} and \function{issubclass()}
-functions don't work properly on ExtensionClasses.  Solution: use
-custom \function{isinstance()} and \function{issubclass()} functions
-that handle ExtensionClasses correctly.
-
 \item Recent versions of the ZODB allow writing a class with 
 \method{__setattr__} , \method{__getattr__}, or \method{__delattr__} methods.  (Older versions didn't support this at all.)
 If you write such a \method{__setattr__} or \method{__delattr__} method, 
@@ -414,100 +381,6 @@ instances as possible, they are still not instances, and
 no attempt is ever made to call \method{__cmp__}.  Perhaps Python 2.2
 will repair this.
 
-\subsubsection{Fixing \function{isinstance} and \function{issubclass}}
-
-Python's built-in functions 
-\function{isinstance()} and \function{issubclass} don't
-work on ExtensionClass instances, for much the same reason that 
-\method{__cmp__} is never called; in some bits of the Python core code,
-branches are taken only if an object is of the \class{InstanceType}
-type, and this can never be true for an ExtensionClass instance.
-Python 2.1 tried to fix this, and changed these functions slightly in
-an effort to make them work for ExtensionClasses; unfortunately, the
-changes didn't work.
-
-The solution is to use customized versions of these functions that
-handle ExtensionClasses specially and fall back to the built-in
-version otherwise.  Here are the versions we've written at the MEMS Exchange:
-
-\begin{verbatim}
-# The built-in 'isinstance()' and 'issubclass()' won't work on
-# ExtensionClasses, so you have to use the versions supplied here.
-# (But those versions work fine on regular instances and classes too,
-# so you should *always* use them.)
-
-def issubclass (class1, class2):
-    """A version of 'issubclass' that works with extension classes
-    as well as regular Python classes.
-    """
-
-    # Both class objects are regular Python classes, so use the
-    # built-in 'issubclass()'.
-    if type(class1) is ClassType and type(class2) is ClassType:
-        return __builtin__.issubclass(class1, class2)
-
-    # Both so-called class objects have a '__bases__' attribute: ie.,
-    # they aren't regular Python classes, but they sure look like them.
-    # Assume they are extension classes and reimplement what the builtin
-    # 'issubclass()' does behind the scenes.
-    elif hasattr(class1, '__bases__') and hasattr(class2, '__bases__'):
-        # XXX it appears that "ec.__class__ is type(ec)" for an
-        # extension class 'ec': could we/should we use this as an
-        # additional check for extension classes?
-
-        # Breadth-first traversal of class1's superclass tree.  Order
-        # doesn't matter because we're just looking for a "yes/no"
-        # answer from the tree; if we were trying to resolve a name,
-        # order would be important!
-        stack = [class1]
-        while stack:
-            if stack[0] is class2:
-                return 1
-            stack.extend(list(stack[0].__bases__))
-            del stack[0]
-        else:
-            return 0
-
-    # Not a regular class, not an extension class: blow up for consistency
-    # with builtin 'issubclass()"
-    else:
-        raise TypeError, "arguments must be class or ExtensionClass objects"
-
-# issubclass ()
-
-def isinstance (object, klass):
-    """A version of 'isinstance' that works with extension classes
-    as well as regular Python classes."""
-
-    if type(klass) is TypeType:
-        return __builtin__.isinstance(object, klass)
-    elif hasattr(object, '__class__'):
-        return issubclass(object.__class__, klass)
-    else:
-        return 0
-\end{verbatim}
-
-I'd recommend putting these functions in a module that always gets
-imported.  The convention on my work project is to put them in
-\file{mems/lib/base.py}, which contains various fundamental classes
-and functions for our system, and access them like this:
-
-\begin{verbatim}
-from mems.lib import base
-...
-if base.isinstance(object, Class): ...
-\end{verbatim}
-
-Don't insert the modified functions into Python's
-\module{__builtin__} module, or import just the
-\function{isinstance()} and \function{issubclass} functions.  
-If you consistently use \function{base.isinstance()}, then forgetting
-to import the \module{base} module will result in a
-\exception{NameError} exception.  In the
-case of a forgotten import, calling the functions directly would use
-Python's built-in versions, leading to subtle bugs that might not be
-noticed for some time.
-
 \subsubsection{\method{__getattr__}, \method{__delattr__}, and \method{__setattr__}}
 
 Recent versions of ZODB allow writing persistent classes that have
@@ -545,7 +418,7 @@ update them to match the new schema.  This can be easy if your network
 of object references is quite structured, making it easy to find all
 the instances of the class being modified.  For example, if all
 \class{User} objects can be found inside a single dictionary or
-B-tree, then it would be a simple matter to loop over every
+BTree, then it would be a simple matter to loop over every
 \class{User} instance with a \keyword{for} statement.
 This is more difficult if your object graph is less structured; if
 \class{User} objects can be found as attributes of any number of

doc/guide/transactions.tex

@@ -103,6 +103,16 @@ transaction''.  Usually this will happen because later transactions
 modified the objects affected by the transaction you're trying to
 undo.
 
+After you call \method{undo()} you must commit the transaction for the
+undo to actually be applied.
+\footnote{There are actually two different ways a storage can
+implement the undo feature.  Most of the storages that ship with ZODB
+use the transactional form of undo described in the main text.  Some
+storages may use a non-transactional undo makes changes visible
+immediately.}  There is one glitch in the undo process.  The thread
+that calls undo may not see the changes to the object until it calls
+\method{Connection.sync()} or commits another transaction.
+
 \subsection{Versions}
 
 While many subtransactions can be contained within a single regular
@@ -161,6 +171,3 @@ The \class{Storage} and \class{DB} instances can be shared among
 several threads, as long as individual \class{Connection} instances
 are created for each thread.  
 
-XXX I can't think of anything else to say about multithreaded ZODB
-programs.  Suggestions?  An example program?
-

doc/guide/zeo.tex

@@ -18,22 +18,21 @@ them in a distributed fashion without Zope ever entering the picture.
 The combination of ZEO and ZODB is essentially a Python-specific
 object database.
 
-ZEO consists of about 1400 lines of Python code.  The code is
-relatively small because it contains only code for a TCP/IP server,
-and for a new type of Storage, \class{ClientStorage}.
-\class{ClientStorage} doesn't use disk files at all; it simply
-makes remote procedure calls to the server, which then passes them on
-a regular \class{Storage} class such as \class{FileStorage}.  The
-following diagram lays out the system:
+ZEO consists of about 6000 lines of Python code, excluding tests.  The
+code is relatively small because it contains only code for a TCP/IP
+server, and for a new type of Storage, \class{ClientStorage}.
+\class{ClientStorage} simply makes remote procedure calls to the
+server, which then passes them on a regular \class{Storage} class such
+as \class{FileStorage}.  The following diagram lays out the system:
 
 XXX insert diagram here later
 
 Any number of processes can create a \class{ClientStorage}
 instance, and any number of threads in each process can be using that
 instance.  \class{ClientStorage} aggressively caches objects
-locally, so in order to avoid using stale data, the ZEO server sends
-an invalidate message to all the connected \class{ClientStorage}
-instances on every write operation.  The invalidate message contains
+locally, so in order to avoid using stale data.  The ZEO server sends
+an invalidation message to all the connected \class{ClientStorage}
+instances on every write operation.  The invalidation message contains
 the object ID for each object that's been modified, letting the
 \class{ClientStorage} instances delete the old data for the
 given object from their caches.
@@ -46,7 +45,9 @@ writes, and ZEO is therefore better suited for read-intensive
 applications.  If every \class{ClientStorage} is writing to the
 database all the time, this will result in a storm of invalidate
 messages being sent, and this might take up more processing time than
-the actual database operations themselves.
+the actual database operations themselves.\footnote{These messages are
+small and sent in batches, so there would need to be a lot of writes
+before it became a problem.}
 
 On the other hand, for applications that have few writes in comparison
 to the number of read accesses, this aggressive caching can be a major
@@ -69,35 +70,16 @@ configure and run a ZEO Storage Server on a machine.
 
 \subsubsection{Requirements}
 
-To run a ZEO server, you'll need Python 1.5.2 or 2.0, and the ZODB
-packages from \url{http://www.amk.ca/files/zodb/}
-have to be installed.  
+The ZEO server software is included in ZODB3.  As with the rest of
+ZODB3, you'll need Python 2.1 or higher.
 
-\emph{Note for Python 1.5.2 users}: ZEO requires updated versions
-of the \module{asyncore.py} and \module{asynchat.py} modules that are
-included in 1.5.2's standard library.  Current versions of the ZODB
-distribution install private versions of these modules, so you
-shouldn't need to grab updated versions yourself.  (The symptom of
-this problem is a traceback on attempting to run a ZEO client program:
-the traceback is ``TypeError: too many arguments; expected 2, got 3''
-around line 100 of \file{smac.py}.
+\subsubsection{Running a server}
 
-\subsubsection{Installation}
-
-Installing the ZEO package is easy.  Just run \code{python setup.py
-install}.  This will install the ZEO/ package into your Python
-installation, and copy various files into their proper locations:
-\file{zeo.conf} will be put into \file{/usr/local/etc/}, a \file{zeo} startup
-script will be put in \file{/etc/rc.d/init.d/}, and the \file{zeod}
-daemon program will be placed in \file{/usr/local/bin}.
-
-\subsection{Configuring and Running a ZEO Server}
-
-Edit \code{/usr/local/etc/zeo.conf} appropriately for your desired
-setup.  This configuration file controls the port on which ZEO will
-listen for connections, the user and group IDs under which the server
-will be executed, and the location of the concrete \class{Storage}
-object that will be made network-accessible.
+The start.py script in the ZEO directory can be used to start a
+server.  Run it with the -h option to see the various values.  If
+you're just experimenting, a good choise is to use 
+\code{python ZEO/start.py -D -U /tmp/zeosocket} to run ZEO in
+debug mode and with a Unix domain socket.
 
 \subsection{Testing the ZEO Installation}
 
@@ -137,15 +119,15 @@ If this code runs properly, then your ZEO server is working correctly.
 
 \subsection{ZEO Programming Notes}
 
-XXX The Connection.sync() method and its necessity (if it works at all!) 
-
-% That doesn't work.  I tested it.  sync() doesn't seem to get into
-% the asyncore loop.  One of us should probably look into adding an
-% API for this when we have some free time.  It would be a nice
-% small project that would get into ZODB's guts.
-
-
-
+ZEO is written using \module{asyncore}, from the Python standard
+library.  It assumes that some part of the user application is running
+an \module{asyncore} mainloop.  For example, Zope run the loop in a
+separate thread and ZEO uses that.  If your application does not have
+a mainloop, ZEO will not process incoming invalidation messages until
+you make some call into ZEO.  The \method{Connection.sync} method can
+be used to process pending invalidation messages.  You can call it
+when you want to make sure the \class{Connection} has the most recent
+version of every object, but you don't have any other work for ZEO to do.
 
 \subsection{Sample Application: chatter.py}
 
@@ -174,7 +156,7 @@ class ChatSession(Persistent):
     def __init__(self, name):
         self.name = name
         # Internal attribute: _messages holds all the chat messages.        
-        self._messages = BTree.BTree()        
+        self._messages = BTrees.OOBTree.OOBTree()        
 \end{verbatim}
 
 \method{add_message()} has to add a message to the

doc/guide/zodb.tex

 \documentclass{howto}
 
 \title{ZODB/ZEO Programming Guide}
-\release{0.03}
+\release{0.04}
 \date{\today}
 
 \author{A.M.\ Kuchling}

doc/guide/zodb/about.html

@@ -6,19 +6,20 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="previous" HREF="node41.html">
+<LINK REL="previous" HREF="node39.html">
 <LINK REL="up" HREF="zodb.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
 <tr>
-<td><A HREF="node53.html"><img src="/python/writing/icons/previous.gif"
+<td><A HREF="node51.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
 <td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
@@ -38,7 +39,7 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node53.html">ADDENDUM: How to use</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node51.html">ADDENDUM: How to use</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
 <br><hr>
 </DIV>
@@ -48,7 +49,7 @@
 About this document ...</A>
 </H1>
  <strong>ZODB/ZEO Programming Guide</strong>,
-February 8, 2002, Release 0.03
+October 4, 2002, Release 0.04
 <p> This document was generated using the <a
     href="http://saftsack.fs.uni-bayreuth.de/~latex2ht/">
     <strong>LaTeX</strong>2<tt>HTML</tt></a> translator.
@@ -78,7 +79,7 @@ February 8, 2002, Release 0.03
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
 <tr>
-<td><A HREF="node53.html"><img src="/python/writing/icons/previous.gif"
+<td><A HREF="node51.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
 <td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
@@ -98,10 +99,10 @@ February 8, 2002, Release 0.03
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node53.html">ADDENDUM: How to use</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node51.html">ADDENDUM: How to use</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/contents.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="zodb.html">
 <LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node2.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -66,45 +67,44 @@ Contents</A>
 <LI><A href="node13.html">2.3 Opening a ZODB</a>
 <LI><A href="node14.html">2.4 Writing a Persistent Class</a>
 <LI><A href="node15.html">2.5 Rules for Writing Persistent Classes</a>
-<LI><A href="node20.html">2.6 Writing Persistent Classes</a>
+<LI><A href="node19.html">2.6 Writing Persistent Classes</a>
 </ul>
 <LI><A href="zeo.html">3 ZEO</a>
 <UL>
-<LI><A href="node23.html">3.1 How ZEO Works</a>
-<LI><A href="node24.html">3.2 Installing ZEO</a>
-<LI><A href="node27.html">3.3 Configuring and Running a ZEO Server</a>
-<LI><A href="node28.html">3.4 Testing the ZEO Installation</a>
-<LI><A href="node29.html">3.5 ZEO Programming Notes</a>
-<LI><A href="node30.html">3.6 Sample Application: chatter.py</a>
+<LI><A href="node22.html">3.1 How ZEO Works</a>
+<LI><A href="node23.html">3.2 Installing ZEO</a>
+<LI><A href="node26.html">3.3 Testing the ZEO Installation</a>
+<LI><A href="node27.html">3.4 ZEO Programming Notes</a>
+<LI><A href="node28.html">3.5 Sample Application: chatter.py</a>
 </ul>
-<LI><A href="node31.html">4 Transactions and Versioning</a>
+<LI><A href="node29.html">4 Transactions and Versioning</a>
 <UL>
-<LI><A href="node32.html">4.1 Subtransactions</a>
-<LI><A href="node33.html">4.2 Undoing Changes</a>
-<LI><A href="node34.html">4.3 Versions</a>
-<LI><A href="node35.html">4.4 Multithreaded ZODB Programs</a>
+<LI><A href="node30.html">4.1 Subtransactions</a>
+<LI><A href="node31.html">4.2 Undoing Changes</a>
+<LI><A href="node32.html">4.3 Versions</a>
+<LI><A href="node33.html">4.4 Multithreaded ZODB Programs</a>
 </ul>
-<LI><A href="node36.html">5 Related Modules</a>
+<LI><A href="node34.html">5 Related Modules</a>
 <UL>
-<LI><A href="node37.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
-<LI><A href="node38.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
-<LI><A href="node39.html">5.3 B-tree Modules</a>
+<LI><A href="node35.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
+<LI><A href="node36.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
+<LI><A href="node37.html">5.3 BTrees Package</a>
 </ul>
-<LI><A href="node40.html">A. Resources</a>
-<LI><A href="node41.html">B. GNU Free Documentation License</a>
+<LI><A href="node38.html">A. Resources</a>
+<LI><A href="node39.html">B. GNU Free Documentation License</a>
 <UL>
-<LI><A href="node42.html">Preamble</a>
-<LI><A href="node43.html">B..1 Applicability and Definitions</a>
-<LI><A href="node44.html">B..2 Verbatim Copying</a>
-<LI><A href="node45.html">B..3 Copying in Quantity</a>
-<LI><A href="node46.html">B..4 Modifications</a>
-<LI><A href="node47.html">B..5 Combining Documents</a>
-<LI><A href="node48.html">B..6 Collections of Documents</a>
-<LI><A href="node49.html">B..7 Aggregation With Independent Works</a>
-<LI><A href="node50.html">B..8 Translation</a>
-<LI><A href="node51.html">B..9 Termination</a>
-<LI><A href="node52.html">B..10 Future Revisions of This Licence</a>
-<LI><A href="node53.html">ADDENDUM: How to use this License for your documents</a>
+<LI><A href="node40.html">Preamble</a>
+<LI><A href="node41.html">B..1 Applicability and Definitions</a>
+<LI><A href="node42.html">B..2 Verbatim Copying</a>
+<LI><A href="node43.html">B..3 Copying in Quantity</a>
+<LI><A href="node44.html">B..4 Modifications</a>
+<LI><A href="node45.html">B..5 Combining Documents</a>
+<LI><A href="node46.html">B..6 Collections of Documents</a>
+<LI><A href="node47.html">B..7 Aggregation With Independent Works</a>
+<LI><A href="node48.html">B..8 Translation</a>
+<LI><A href="node49.html">B..9 Termination</a>
+<LI><A href="node50.html">B..10 Future Revisions of This Licence</a>
+<LI><A href="node51.html">ADDENDUM: How to use this License for your documents</a>
 </ul>
 <LI><A href="about.html">About this document ...</a>
 </ul>
@@ -147,7 +147,7 @@ Contents</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node2.html">1 Introduction</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/images.tex

@@ -5,7 +5,7 @@
 
 
 \title{ZODB/ZEO Programming Guide}
-\release{0.03}
+\release{0.04}
 \date{\today}
 
 \author{A.M.\ Kuchling}\authoraddress{akuchlin@mems-exchange.org}
@@ -150,7 +150,6 @@
 \stepcounter{subsubsection}
 \stepcounter{subsubsection}
 \stepcounter{subsubsection}
-\stepcounter{subsubsection}
 \stepcounter{subsection}
 \stepcounter{subsubsection}
 \stepcounter{section}
@@ -161,7 +160,6 @@
 \stepcounter{subsection}
 \stepcounter{subsection}
 \stepcounter{subsection}
-\stepcounter{subsection}
 \stepcounter{section}
 \stepcounter{subsection}
 \stepcounter{subsection}
@@ -175,7 +173,7 @@
 \stepcounter{section}
 \stepcounter{section}
 {\newpage\clearpage
-\lthtmlinlinemathA{tex2html_wrap_inline847}%
+\lthtmlinlinemathA{tex2html_wrap_inline807}%
 $\copyright$%
 \lthtmlinlinemathZ
 \lthtmlcheckvsize\clearpage}

doc/guide/zodb/index.html

@@ -6,12 +6,13 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" href="contents.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -47,8 +48,8 @@
 <h1>ZODB/ZEO Programming Guide</h1>
 <p><b><font size="+2">A.M. Kuchling</font></b></p>
 <p>akuchlin@mems-exchange.org</p>
-<p><strong>Release 0.03</strong><br>
-<strong>February 8, 2002</strong></p>
+<p><strong>Release 0.04</strong><br>
+<strong>October 4, 2002</strong></p>
 <p>
 </center>
 </div>
@@ -81,55 +82,53 @@
 <UL>
 <LI><A href="node16.html">2.5.1 Modifying Mutable Objects</a>
 <LI><A href="node17.html">2.5.2 Some Special Methods Don't Work</a>
-<LI><A href="node18.html">2.5.3 Fixing <tt class="function">isinstance</tt> and <tt class="function">issubclass</tt></a>
-<LI><A href="node19.html">2.5.4 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
+<LI><A href="node18.html">2.5.3 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
 </ul>
-<LI><A href="node20.html">2.6 Writing Persistent Classes</a>
+<LI><A href="node19.html">2.6 Writing Persistent Classes</a>
 <UL>
-<LI><A href="node21.html">2.6.1 Changing Instance Attributes</a>
+<LI><A href="node20.html">2.6.1 Changing Instance Attributes</a>
 </ul>
 </ul>
 <LI><A href="zeo.html">3 ZEO</a>
 <UL>
-<LI><A href="node23.html">3.1 How ZEO Works</a>
-<LI><A href="node24.html">3.2 Installing ZEO</a>
+<LI><A href="node22.html">3.1 How ZEO Works</a>
+<LI><A href="node23.html">3.2 Installing ZEO</a>
 <UL>
-<LI><A href="node25.html">3.2.1 Requirements</a>
-<LI><A href="node26.html">3.2.2 Installation</a>
+<LI><A href="node24.html">3.2.1 Requirements</a>
+<LI><A href="node25.html">3.2.2 Running a server</a>
 </ul>
-<LI><A href="node27.html">3.3 Configuring and Running a ZEO Server</a>
-<LI><A href="node28.html">3.4 Testing the ZEO Installation</a>
-<LI><A href="node29.html">3.5 ZEO Programming Notes</a>
-<LI><A href="node30.html">3.6 Sample Application: chatter.py</a>
+<LI><A href="node26.html">3.3 Testing the ZEO Installation</a>
+<LI><A href="node27.html">3.4 ZEO Programming Notes</a>
+<LI><A href="node28.html">3.5 Sample Application: chatter.py</a>
 </ul>
-<LI><A href="node31.html">4 Transactions and Versioning</a>
+<LI><A href="node29.html">4 Transactions and Versioning</a>
 <UL>
-<LI><A href="node32.html">4.1 Subtransactions</a>
-<LI><A href="node33.html">4.2 Undoing Changes</a>
-<LI><A href="node34.html">4.3 Versions</a>
-<LI><A href="node35.html">4.4 Multithreaded ZODB Programs</a>
+<LI><A href="node30.html">4.1 Subtransactions</a>
+<LI><A href="node31.html">4.2 Undoing Changes</a>
+<LI><A href="node32.html">4.3 Versions</a>
+<LI><A href="node33.html">4.4 Multithreaded ZODB Programs</a>
 </ul>
-<LI><A href="node36.html">5 Related Modules</a>
+<LI><A href="node34.html">5 Related Modules</a>
 <UL>
-<LI><A href="node37.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
-<LI><A href="node38.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
-<LI><A href="node39.html">5.3 B-tree Modules</a>
+<LI><A href="node35.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
+<LI><A href="node36.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
+<LI><A href="node37.html">5.3 BTrees Package</a>
 </ul>
-<LI><A href="node40.html">A. Resources</a>
-<LI><A href="node41.html">B. GNU Free Documentation License</a>
+<LI><A href="node38.html">A. Resources</a>
+<LI><A href="node39.html">B. GNU Free Documentation License</a>
 <UL>
-<LI><A href="node42.html">Preamble</a>
-<LI><A href="node43.html">B..1 Applicability and Definitions</a>
-<LI><A href="node44.html">B..2 Verbatim Copying</a>
-<LI><A href="node45.html">B..3 Copying in Quantity</a>
-<LI><A href="node46.html">B..4 Modifications</a>
-<LI><A href="node47.html">B..5 Combining Documents</a>
-<LI><A href="node48.html">B..6 Collections of Documents</a>
-<LI><A href="node49.html">B..7 Aggregation With Independent Works</a>
-<LI><A href="node50.html">B..8 Translation</a>
-<LI><A href="node51.html">B..9 Termination</a>
-<LI><A href="node52.html">B..10 Future Revisions of This Licence</a>
-<LI><A href="node53.html">ADDENDUM: How to use this License for your documents</a>
+<LI><A href="node40.html">Preamble</a>
+<LI><A href="node41.html">B..1 Applicability and Definitions</a>
+<LI><A href="node42.html">B..2 Verbatim Copying</a>
+<LI><A href="node43.html">B..3 Copying in Quantity</a>
+<LI><A href="node44.html">B..4 Modifications</a>
+<LI><A href="node45.html">B..5 Combining Documents</a>
+<LI><A href="node46.html">B..6 Collections of Documents</a>
+<LI><A href="node47.html">B..7 Aggregation With Independent Works</a>
+<LI><A href="node48.html">B..8 Translation</a>
+<LI><A href="node49.html">B..9 Termination</a>
+<LI><A href="node50.html">B..10 Future Revisions of This Licence</a>
+<LI><A href="node51.html">ADDENDUM: How to use this License for your documents</a>
 </ul>
 <LI><A href="about.html">About this document ...</a>
 </ul>
@@ -161,7 +160,7 @@
 </tr></table>
 <b class="navlabel">Next:</b> <a class="sectref" href="contents.html">Contents</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node10.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node9.html">
 <LINK REL="up" HREF="node9.html">
 <LINK REL="next" HREF="node11.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -52,36 +53,15 @@
 </H3>
 
 <P>
-You'll need Python, of course; version 1.5.2 works with some fixes,
-and it also works with Python 2.0, which is what I primarily use.
-
-<P>
-The code is packaged using Distutils, the new distribution tools for
-Python introduced in Python 2.0.  If you're using 1.5.2, first you'll
-have to get the latest Distutils release from the Distutils SIG page
-at <a class="url" href="http://www.python.org/sigs/distutils-sig/download.html">http://www.python.org/sigs/distutils-sig/download.html</a> and
-install it.  This is simply a matter of untarring or unzipping the
+You will need Python 2.1 or higher.  The code is packaged using
+Distutils.  So it is simply a matter of untarring or unzipping the
 release package, and then running <code>python setup.py install</code>.
 
-<P>
-If you're using 1.5.2 and have installed previous versions of the
-Distutils, be sure to get the very latest version, since developing
-the ZODB distribution turned up some bugs along the way.  If you
-encounter problems compiling <span class="file">ZODB/TimeStamp.c</span> or your compiler reports
-an error like ``Can't create build/temp.linux2/ExtensionClass.o: No
-such file or directory'', you need an updated version.  Old versions of
-Distutils have two bugs which affect the setup scripts.  First, for a
-long time the <code>define_macros</code> keyword in setup.py files didn't work due
-to a Distutils bug, so I hacked TimeStamp.c in earlier releases.  The
-Distutils have since been fixed, and the hack became unnecessary, so I
-removed it.  Second, the code that creates directories tries to be
-smart and caches them to save time by not trying to create a directory
-twice, but this code was broken in old versions.
-
 <P>
 You'll need a C compiler to build the packages, because there are
 various C extension modules.  At the moment no one is making Windows
-binaries available, so you'll need a Windows development environment to use the 
+binaries available, so you'll need a Windows development environment
+to build ZODB.
 
 <P>
 
@@ -113,7 +93,7 @@ binaries available, so you'll need a Windows development environment to use the
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node9.html">2.1 Installing ZODB</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node11.html">2.1.2 Installing the Packages</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node11.html

@@ -6,14 +6,15 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="previous" HREF="node10.html">
 <LINK REL="up" HREF="node9.html">
 <LINK REL="next" HREF="node12.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -52,38 +53,9 @@
 
 <P>
 Download the ZODB tarball containing all the packages for both ZODB
-and ZEO from <a class="url" href="http://www.amk.ca/files/zodb/">http://www.amk.ca/files/zodb/</a>.
-
-<P>
-To build the packages, you must go into the individual directories and
-build and install them one by one.  They should be built and installed
-in this order:
-
-<P>
-
-<OL>
-<LI><code>zodb-basic</code>
-</LI>
-<LI>ExtensionClass
-</LI>
-<LI>ZODB
-</LI>
-<LI><code>BTree</code> and <code>BTrees</code>
-</LI>
-<LI>ZEO
-</LI>
-</OL>
-
-<P>
-In particular, you must install ExtensionClass before building the
-ZODB package; otherwise, the compilation in the ZODB package will die
-complaining that it can't find ExtensionClass.h.  You can manually
-hack the #include path to make it work without installing
-ExtensionClass first, but that's a bit hackish.
-
-<P>
-If you encounter any problems, please let me know at
-<span class="email">akuchlin@mems-exchange.org</span>.
+and ZEO from <a class="url" href="http://www.zope.org/Products/StandaloneZODB">http://www.zope.org/Products/StandaloneZODB</a>.  See
+the <span class="file">README.txt</span> file in the top level of the release directory
+for details on building, testing, and installing.
 
 <P>
 
@@ -115,7 +87,7 @@ If you encounter any problems, please let me know at
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node9.html">2.1 Installing ZODB</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node12.html">2.2 How ZODB Works</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node12.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node9.html">
 <LINK REL="up" HREF="node8.html">
 <LINK REL="next" HREF="node13.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -91,10 +92,16 @@ state.
 <DT>Consistency</DT>
 <DD>means that the data cannot be placed into a
 logically invalid state; sanity checks can be written and enforced.
-Usually this is done by defining a database schema, and requiring the
-data always matches the schema.  For example, this might enforce that
-the <code>order_number</code> attribute is always an integer, and not a
-string, tuple, or other object.
+Usually this is done by defining a database schema, and requiring
+the data always matches the schema.  There are two typical
+approaches to consistency.  One is to enforce rules about the types
+of objects and attribute; for example, enforce that the
+<code>order_number</code> attribute is always an integer, and not a
+string, tuple, or other object.  Another is to guarantee consistency
+across data structures; for example, that any object with an
+<code>order_number</code> attribute must also appear in the
+<code>orders_table</code> object.  In general, atomicity and isolation make
+it possible for applications to provide consistency.
 
 <P>
 </DD>
@@ -148,7 +155,7 @@ has no way of enforcing consistency with a schema.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node13.html">2.3 Opening a ZODB</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node13.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node12.html">
 <LINK REL="up" HREF="node8.html">
 <LINK REL="next" HREF="node14.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -65,7 +66,7 @@ implement the <tt class="class">Storage</tt> interface.
  storing and retrieving objects from some form of long-term storage.
  A few different types of Storage have been written, such as
  <tt class="class">FileStorage</tt>, which uses regular disk files, and
- <tt class="class">BerkeleyStorage</tt>, which uses Sleepycat Software's BerkeleyDB
+ <tt class="class">bsddb3Storage</tt>, which uses Sleepycat Software's BerkeleyDB
  database.  You could write a new Storage that stored objects in a
  relational database or Metakit file, for example, if that would
  better suit your application.  Two example storages,
@@ -81,7 +82,7 @@ implement the <tt class="class">Storage</tt> interface.
 <P>
 </LI>
 <LI>Finally, the <tt class="class">Connection</tt> class caches objects, and moves
- them into and out of object storage.  A multi-threaded program can
+ them into and out of object storage.  A multi-threaded program should
  open a separate <tt class="class">Connection</tt> instance for each thread.
  Different threads can then modify objects and commit their
  modifications independently.
@@ -97,13 +98,13 @@ a <tt class="class">Connection</tt> from the <tt class="class">DB instance</tt>.
 code:
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
 from ZODB import FileStorage, DB
 
 storage = FileStorage.FileStorage('/tmp/test-filestorage.fs')
 db = DB(storage)
 conn = db.open()
-</pre></dl>
+</pre></div>
 
 <P>
 Note that you can use a completely different data storage mechanism by
@@ -141,7 +142,7 @@ you'll see how ZEO uses this flexibility to good effect.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node14.html">2.4 Writing a Persistent</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node14.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node13.html">
 <LINK REL="up" HREF="node8.html">
 <LINK REL="next" HREF="node15.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -56,13 +57,13 @@ Making a Python class persistent is quite simple; it simply needs to
 subclass from the <tt class="class">Persistent</tt> class, as shown in this example:
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
 import ZODB
 from Persistence import Persistent
 
 class User(Persistent):
     pass
-</pre></dl>
+</pre></div>
 
 <P>
 The apparently unnecessary <code>import ZODB</code> statement is
@@ -70,6 +71,11 @@ needed for the following <code>from...import</code> statement to work
 correctly, since the ZODB code does some magical tricks with
 importing.
 
+<P>
+The <tt class="class">Persistent</tt> base class is an <tt class="module">ExtensionClass</tt>
+class.  As a result, it not compatible with new-style classes or types
+in Python 2.2 and up.
+
 <P>
 For simplicity, in the examples the <tt class="class">User</tt> class will
 simply be used as a holder for a bunch of attributes.  Normally the
@@ -96,7 +102,7 @@ that will contain all the <tt class="class">User</tt> objects.  (The
 <tt class="class">BTree</tt> module is also included as part of Zope.)
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
 dbroot = conn.root()
 
 # Ensure that a 'userdb' key is present 
@@ -106,7 +112,7 @@ if not dbroot.has_key('userdb'):
     dbroot['userdb'] = BTree.BTree()
 
 userdb = dbroot['userdb']
-</pre></dl>
+</pre></div>
 
 <P>
 Inserting a new user is simple: create the <tt class="class">User</tt> object, fill
@@ -114,7 +120,7 @@ it with data, insert it into the <tt class="class">BTree</tt> instance, and comm
 this transaction.
 
 <P>
-<dl><dd><pre class="verbatim"># Create new User instance
+<div class="verbatim"><pre># Create new User instance
 newuser = User() 
 
 # Add whatever attributes you want to track
@@ -127,7 +133,7 @@ userdb[newuser.id] = newuser
 
 # Commit the change
 get_transaction().commit()
-</pre></dl>
+</pre></div>
 
 <P>
 When you import the ZODB package, it adds a new function,
@@ -146,7 +152,7 @@ having transactional semantics for your program's variables, and you
 can experiment with transactions at the Python interpreter's prompt:
 
 <P>
-<dl><dd><pre class="verbatim">&gt;&gt;&gt; newuser
+<div class="verbatim"><pre>&gt;&gt;&gt; newuser
 &lt;User instance at 81b1f40&gt;
 &gt;&gt;&gt; newuser.first_name           # Print initial value
 'Andrew'         
@@ -156,7 +162,7 @@ can experiment with transactions at the Python interpreter's prompt:
 &gt;&gt;&gt; get_transaction().abort()    # Abort transaction
 &gt;&gt;&gt; newuser.first_name           # The value has changed back
 'Andrew'
-</pre></dl>
+</pre></div>
 
 <P>
 
@@ -188,7 +194,7 @@ can experiment with transactions at the Python interpreter's prompt:
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node15.html

@@ -6,15 +6,16 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node20.html">
+<LINK REL="next" HREF="node19.html">
 <LINK REL="previous" HREF="node14.html">
 <LINK REL="up" HREF="node8.html">
 <LINK REL="next" HREF="node16.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -81,13 +82,6 @@ defined on ExtensionClasses.  The most important ones are the
 arithmetic operations: <tt class="method">__radd__</tt>, <tt class="method">__rsub__</tt>, and so
 forth.
 
-<P>
-</LI>
-<LI>Python's built-in <tt class="function">isinstance()</tt> and <tt class="function">issubclass()</tt>
-functions don't work properly on ExtensionClasses.  Solution: use
-custom <tt class="function">isinstance()</tt> and <tt class="function">issubclass()</tt> functions
-that handle ExtensionClasses correctly.
-
 <P>
 </LI>
 <LI>Recent versions of the ZODB allow writing a class with 
@@ -111,8 +105,7 @@ Let's look at each of these rules in detail.
 <UL>
 <LI><A href="node16.html">2.5.1 Modifying Mutable Objects</a>
 <LI><A href="node17.html">2.5.2 Some Special Methods Don't Work</a>
-<LI><A href="node18.html">2.5.3 Fixing <tt class="function">isinstance</tt> and <tt class="function">issubclass</tt></a>
-<LI><A href="node19.html">2.5.4 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
+<LI><A href="node18.html">2.5.3 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
 </ul>
 <!--End of Table of Child-Links-->
 
@@ -144,7 +137,7 @@ Let's look at each of these rules in detail.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node16.html">2.5.1 Modifying Mutable Objects</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node16.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node15.html">
 <LINK REL="up" HREF="node15.html">
 <LINK REL="next" HREF="node17.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -77,10 +78,10 @@ its dirty bit to true.  This is done by setting the
 <tt class="member">_p_changed</tt> attribute of the object to true:
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
 userobj.friends.append(otherUser)
 userobj._p_changed = 1
-</pre></dl>
+</pre></div>
 
 <P>
 An obsolete way of doing this that's still supported is calling the
@@ -98,11 +99,11 @@ an <tt class="method">add_friend()</tt> modifier method to the class.  <tt class
 would then look like this:
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
     def add_friend(self, friend):
         self.friends.append(otherUser)
         self._p_changed = 1
-</pre></dl>
+</pre></div>
 
 <P>
 Alternatively, you could use a ZODB-aware list or mapping type that
@@ -141,7 +142,7 @@ and may make it into a future upstream release of Zope.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node17.html">2.5.2 Some Special Methods</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node17.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node16.html">
 <LINK REL="up" HREF="node15.html">
 <LINK REL="next" HREF="node18.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -42,7 +43,7 @@
 </tr></table>
 <b class="navlabel">Previous:</b> <a class="sectref" HREF="node16.html">2.5.1 Modifying Mutable Objects</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node18.html">2.5.3 Fixing isinstance and</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node18.html">2.5.3 __getattr__, __delattr__, and</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
@@ -77,13 +78,13 @@ instances, which means that <code>type(obj) == types.InstanceType</code>.
 The code inside the Python interpreter looks like this:
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
 /* Code to compare objects v and w */
 if (PyInstance_Check(v) || PyInstance_Check(w))
         return PyInstance_DoBinOp(v, w, "__cmp__", "__rcmp__", do_cmp);
 /* Do usual Python comparison of v,w */
 c = PyObject_Compare(v, w);
-</pre></dl>
+</pre></div>
 
 <P>
 While ExtensionClasses try to behave as much like regular Python
@@ -120,9 +121,9 @@ will repair this.
 </tr></table>
 <b class="navlabel">Previous:</b> <a class="sectref" HREF="node16.html">2.5.1 Modifying Mutable Objects</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node18.html">2.5.3 Fixing isinstance and</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node18.html">2.5.3 __getattr__, __delattr__, and</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node18.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>2.5.3 Fixing isinstance and issubclass</title>
-<META NAME="description" CONTENT="2.5.3 Fixing isinstance and issubclass">
+<title>2.5.3 __getattr__, __delattr__, and __setattr__</title>
+<META NAME="description" CONTENT="2.5.3 __getattr__, __delattr__, and __setattr__">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node19.html">
 <LINK REL="previous" HREF="node17.html">
 <LINK REL="up" HREF="node15.html">
 <LINK REL="next" HREF="node19.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -42,112 +42,24 @@
 </tr></table>
 <b class="navlabel">Previous:</b> <a class="sectref" HREF="node17.html">2.5.2 Some Special Methods</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node19.html">2.5.4 __getattr__, __delattr__, and</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node19.html">2.6 Writing Persistent Classes</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
 <H3><A NAME="SECTION000353000000000000000">
-2.5.3 Fixing <tt class="function">isinstance</tt> and <tt class="function">issubclass</tt></A>
+2.5.3 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></A>
 </H3>
 
 <P>
-Python's built-in functions 
-<tt class="function">isinstance()</tt> and <tt class="function">issubclass</tt> don't
-work on ExtensionClass instances, for much the same reason that 
-<tt class="method">__cmp__</tt> is never called; in some bits of the Python core code,
-branches are taken only if an object is of the <tt class="class">InstanceType</tt>
-type, and this can never be true for an ExtensionClass instance.
-Python 2.1 tried to fix this, and changed these functions slightly in
-an effort to make them work for ExtensionClasses; unfortunately, the
-changes didn't work.
-
-<P>
-The solution is to use customized versions of these functions that
-handle ExtensionClasses specially and fall back to the built-in
-version otherwise.  Here are the versions we've written at the MEMS Exchange:
-
-<P>
-<dl><dd><pre class="verbatim">
-# The built-in 'isinstance()' and 'issubclass()' won't work on
-# ExtensionClasses, so you have to use the versions supplied here.
-# (But those versions work fine on regular instances and classes too,
-# so you should *always* use them.)
-
-def issubclass (class1, class2):
-    """A version of 'issubclass' that works with extension classes
-    as well as regular Python classes.
-    """
-
-    # Both class objects are regular Python classes, so use the
-    # built-in 'issubclass()'.
-    if type(class1) is ClassType and type(class2) is ClassType:
-        return __builtin__.issubclass(class1, class2)
-
-    # Both so-called class objects have a '__bases__' attribute: ie.,
-    # they aren't regular Python classes, but they sure look like them.
-    # Assume they are extension classes and reimplement what the builtin
-    # 'issubclass()' does behind the scenes.
-    elif hasattr(class1, '__bases__') and hasattr(class2, '__bases__'):
-        # XXX it appears that "ec.__class__ is type(ec)" for an
-        # extension class 'ec': could we/should we use this as an
-        # additional check for extension classes?
-
-        # Breadth-first traversal of class1's superclass tree.  Order
-        # doesn't matter because we're just looking for a "yes/no"
-        # answer from the tree; if we were trying to resolve a name,
-        # order would be important!
-        stack = [class1]
-        while stack:
-            if stack[0] is class2:
-                return 1
-            stack.extend(list(stack[0].__bases__))
-            del stack[0]
-        else:
-            return 0
-
-    # Not a regular class, not an extension class: blow up for consistency
-    # with builtin 'issubclass()"
-    else:
-        raise TypeError, "arguments must be class or ExtensionClass objects"
-
-# issubclass ()
-
-def isinstance (object, klass):
-    """A version of 'isinstance' that works with extension classes
-    as well as regular Python classes."""
-
-    if type(klass) is TypeType:
-        return __builtin__.isinstance(object, klass)
-    elif hasattr(object, '__class__'):
-        return issubclass(object.__class__, klass)
-    else:
-        return 0
-</pre></dl>
-
-<P>
-I'd recommend putting these functions in a module that always gets
-imported.  The convention on my work project is to put them in
-<span class="file">mems/lib/base.py</span>, which contains various fundamental classes
-and functions for our system, and access them like this:
-
-<P>
-<dl><dd><pre class="verbatim">
-from mems.lib import base
-...
-if base.isinstance(object, Class): ...
-</pre></dl>
-
-<P>
-Don't insert the modified functions into Python's
-<tt class="module">__builtin__</tt> module, or import just the
-<tt class="function">isinstance()</tt> and <tt class="function">issubclass</tt> functions.  
-If you consistently use <tt class="function">base.isinstance()</tt>, then forgetting
-to import the <tt class="module">base</tt> module will result in a
-<tt class="exception">NameError</tt> exception.  In the
-case of a forgotten import, calling the functions directly would use
-Python's built-in versions, leading to subtle bugs that might not be
-noticed for some time.
+Recent versions of ZODB allow writing persistent classes that have
+<tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, or <tt class="method">__setattr__</tt>
+methods.  The one minor complication is that the machinery for
+automatically detecting changes to the object is disabled while the
+<tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, or <tt class="method">__setattr__</tt>
+method is executing.  This means that if the object is modified, the
+object should be marked as dirty by setting the object's
+<tt class="member">_p_changed</tt> method to true.
 
 <P>
 
@@ -177,9 +89,9 @@ noticed for some time.
 </tr></table>
 <b class="navlabel">Previous:</b> <a class="sectref" HREF="node17.html">2.5.2 Some Special Methods</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node19.html">2.5.4 __getattr__, __delattr__, and</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node19.html">2.6 Writing Persistent Classes</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node19.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>2.5.4 __getattr__, __delattr__, and __setattr__</title>
-<META NAME="description" CONTENT="2.5.4 __getattr__, __delattr__, and __setattr__">
+<title>2.6 Writing Persistent Classes</title>
+<META NAME="description" CONTENT="2.6 Writing Persistent Classes">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="previous" HREF="node18.html">
-<LINK REL="up" HREF="node15.html">
+<LINK REL="previous" HREF="node15.html">
+<LINK REL="up" HREF="node8.html">
 <LINK REL="next" HREF="node20.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -22,7 +23,7 @@
 <td><A HREF="node18.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node15.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node8.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node20.html"><img src="/python/writing/icons/next.gif"
@@ -39,29 +40,33 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node18.html">2.5.3 Fixing isinstance and</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node20.html">2.6 Writing Persistent Classes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node18.html">2.5.3 __getattr__, __delattr__, and</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node20.html">2.6.1 Changing Instance Attributes</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H3><A NAME="SECTION000354000000000000000">
-2.5.4 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></A>
-</H3>
+<H2><A NAME="SECTION000360000000000000000">
+2.6 Writing Persistent Classes</A>
+</H2>
 
 <P>
-Recent versions of ZODB allow writing persistent classes that have
-<tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, or <tt class="method">__setattr__</tt>
-methods.  The one minor complication is that the machinery for
-automatically detecting changes to the object is disabled while the
-<tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, or <tt class="method">__setattr__</tt>
-method is executing.  This means that if the object is modified, the
-object should be marked as dirty by setting the object's
-<tt class="member">_p_changed</tt> method to true.
+Now that we've looked at the basics of programming using the ZODB,
+we'll turn to some more subtle tasks that are likely to come up for
+anyone using the ZODB in a production system.
 
 <P>
 
+<p><hr>
+<!--Table of Child-Links-->
+<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
+
+<UL>
+<LI><A href="node20.html">2.6.1 Changing Instance Attributes</a>
+</ul>
+<!--End of Table of Child-Links-->
+
 <DIV CLASS="navigation">
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
@@ -69,7 +74,7 @@ object should be marked as dirty by setting the object's
 <td><A HREF="node18.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node15.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node8.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node20.html"><img src="/python/writing/icons/next.gif"
@@ -86,11 +91,11 @@ object should be marked as dirty by setting the object's
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node18.html">2.5.3 Fixing isinstance and</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node15.html">2.5 Rules for Writing</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node20.html">2.6 Writing Persistent Classes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node18.html">2.5.3 __getattr__, __delattr__, and</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node20.html">2.6.1 Changing Instance Attributes</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node2.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" href="contents.html">
 <LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node3.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -100,7 +101,7 @@ of the guide is always available at
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node3.html">1.1 What is the</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node20.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>2.6 Writing Persistent Classes</title>
-<META NAME="description" CONTENT="2.6 Writing Persistent Classes">
+<title>2.6.1 Changing Instance Attributes</title>
+<META NAME="description" CONTENT="2.6.1 Changing Instance Attributes">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="previous" HREF="node15.html">
-<LINK REL="up" HREF="node8.html">
-<LINK REL="next" HREF="node21.html">
+<LINK REL="previous" HREF="node19.html">
+<LINK REL="up" HREF="node19.html">
+<LINK REL="next" href="zeo.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -22,10 +23,10 @@
 <td><A HREF="node19.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node8.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node19.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
-<td><A HREF="node21.html"><img src="/python/writing/icons/next.gif"
+<td><A href="zeo.html"><img src="/python/writing/icons/next.gif"
   border="0" height="32"
   alt="Next Page" width="32"></A></td>
 <td align="center" width="100%">ZODB/ZEO Programming Guide</td>
@@ -39,33 +40,65 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node19.html">2.5.4 __getattr__, __delattr__, and</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node21.html">2.6.1 Changing Instance Attributes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node19.html">2.6 Writing Persistent Classes</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node19.html">2.6 Writing Persistent Classes</A>
+<b class="navlabel">Next:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000360000000000000000">
-2.6 Writing Persistent Classes</A>
-</H2>
+<H3><A NAME="SECTION000361000000000000000">
+2.6.1 Changing Instance Attributes</A>
+</H3>
 
 <P>
-Now that we've looked at the basics of programming using the ZODB,
-we'll turn to some more subtle tasks that are likely to come up for
-anyone using the ZODB in a production system.
+Ideally, before making a class persistent you would get its interface
+right the first time, so that no attributes would ever need to be
+added, removed, or have their interpretation change over time.  It's a
+worthy goal, but also an impractical one unless you're gifted with
+perfect knowledge of the future.  Such unnatural foresight can't be
+required of any person, so you therefore have to be prepared to handle
+such structural changes gracefully.  In object-oriented database
+terminology, this is a schema update.  The ZODB doesn't have an actual
+schema specification, but you're changing the software's expectations
+of the data contained by an object, so you're implicitly changing the
+schema.
 
 <P>
+One way to handle such a change is to write a one-time conversion
+program that will loop over every single object in the database and
+update them to match the new schema.  This can be easy if your network
+of object references is quite structured, making it easy to find all
+the instances of the class being modified.  For example, if all
+<tt class="class">User</tt> objects can be found inside a single dictionary or
+BTree, then it would be a simple matter to loop over every
+<tt class="class">User</tt> instance with a <tt class="keyword">for</tt> statement.
+This is more difficult if your object graph is less structured; if
+<tt class="class">User</tt> objects can be found as attributes of any number of
+different class instances, then there's no longer any easy way to find
+them all, short of writing a generalized object traversal function
+that would walk over every single object in a ZODB, checking each one
+to see if it's an instance of <tt class="class">User</tt>.  
+<A NAME="tex2html1"
+  HREF="#foot262"><SUP>1</SUP></A>Some OODBs support a feature called extents, which allow quickly
+finding all the instances of a given class, no matter where they are
+in the object graph; unfortunately the ZODB doesn't offer extents as a
+feature.
 
-<p><hr>
-<!--Table of Child-Links-->
-<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
+<P>
+XXX Rest of section not written yet: __getstate__/__setstate__
 
-<UL>
-<LI><A href="node21.html">2.6.1 Changing Instance Attributes</a>
-</ul>
-<!--End of Table of Child-Links-->
+<P>
+<BR><HR><H4>Footnotes</H4>
+<DL>
+<DT><A NAME="foot262">...User.  
+</A><A NAME="foot262"
+ HREF="node20.html#tex2html1"><SUP>1</SUP></A>
+<DD>XXX is there a convenience method for walking the object graph hiding
+somewhere inside DC's code?  Should there be a utility method for
+doing this?  Should I write one and include it in this section?
 
+</DL>
 <DIV CLASS="navigation">
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
@@ -73,10 +106,10 @@ anyone using the ZODB in a production system.
 <td><A HREF="node19.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node8.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node19.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
-<td><A HREF="node21.html"><img src="/python/writing/icons/next.gif"
+<td><A href="zeo.html"><img src="/python/writing/icons/next.gif"
   border="0" height="32"
   alt="Next Page" width="32"></A></td>
 <td align="center" width="100%">ZODB/ZEO Programming Guide</td>
@@ -90,11 +123,11 @@ anyone using the ZODB in a production system.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node19.html">2.5.4 __getattr__, __delattr__, and</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node21.html">2.6.1 Changing Instance Attributes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node19.html">2.6 Writing Persistent Classes</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node19.html">2.6 Writing Persistent Classes</A>
+<b class="navlabel">Next:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node22.html

+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
+<html>
+<head>
+<title>3.1 How ZEO Works</title>
+<META NAME="description" CONTENT="3.1 How ZEO Works">
+<META NAME="keywords" CONTENT="zodb">
+<META NAME="resource-type" CONTENT="document">
+<META NAME="distribution" CONTENT="global">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
+<link rel="first" href="zodb.html">
+<link rel="contents" href="contents.html" title="Contents">
+
+<LINK REL="next" HREF="node23.html">
+<LINK REL="previous" href="zeo.html">
+<LINK REL="up" href="zeo.html">
+<LINK REL="next" HREF="node23.html">
+<meta name='aesop' content='information'>
+</head>
+<body>
+<DIV CLASS="navigation">
+<table align="center" width="100%" cellpadding="0" cellspacing="2">
+<tr>
+<td><A href="zeo.html"><img src="/python/writing/icons/previous.gif"
+  border="0" height="32"
+  alt="Previous Page" width="32"></A></td>
+<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+  border="0" height="32"
+  alt="Up One Level" width="32"></A></td>
+<td><A HREF="node23.html"><img src="/python/writing/icons/next.gif"
+  border="0" height="32"
+  alt="Next Page" width="32"></A></td>
+<td align="center" width="100%">ZODB/ZEO Programming Guide</td>
+<td><A href="contents.html"><img src="/python/writing/icons/contents.gif"
+  border="0" height="32"
+  alt="Contents" width="32"></A></td>
+<td><img src="/python/writing/icons/blank.gif"
+  border="0" height="32"
+  alt="" width="32"></td>
+<td><img src="/python/writing/icons/blank.gif"
+  border="0" height="32"
+  alt="" width="32"></td>
+</tr></table>
+<b class="navlabel">Previous:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<br><hr>
+</DIV>
+<!--End of Navigation Panel-->
+
+<H2><A NAME="SECTION000410000000000000000">
+3.1 How ZEO Works</A>
+</H2>
+
+<P>
+The ZODB, as I've described it so far, can only be used within a
+single Python process (though perhaps with multiple threads).  ZEO,
+Zope Enterprise Objects, extends the ZODB machinery to provide access
+to objects over a network.  The name "Zope Enterprise Objects" is a
+bit misleading; ZEO can be used to store Python objects and access
+them in a distributed fashion without Zope ever entering the picture.
+The combination of ZEO and ZODB is essentially a Python-specific
+object database.
+
+<P>
+ZEO consists of about 6000 lines of Python code, excluding tests.  The
+code is relatively small because it contains only code for a TCP/IP
+server, and for a new type of Storage, <tt class="class">ClientStorage</tt>.
+<tt class="class">ClientStorage</tt> simply makes remote procedure calls to the
+server, which then passes them on a regular <tt class="class">Storage</tt> class such
+as <tt class="class">FileStorage</tt>.  The following diagram lays out the system:
+
+<P>
+XXX insert diagram here later
+
+<P>
+Any number of processes can create a <tt class="class">ClientStorage</tt>
+instance, and any number of threads in each process can be using that
+instance.  <tt class="class">ClientStorage</tt> aggressively caches objects
+locally, so in order to avoid using stale data.  The ZEO server sends
+an invalidation message to all the connected <tt class="class">ClientStorage</tt>
+instances on every write operation.  The invalidation message contains
+the object ID for each object that's been modified, letting the
+<tt class="class">ClientStorage</tt> instances delete the old data for the
+given object from their caches.
+
+<P>
+This design decision has some consequences you should be aware of.
+First, while ZEO isn't tied to Zope, it was first written for use with
+Zope, which stores HTML, images, and program code in the database.  As
+a result, reads from the database are <i>far</i> more frequent than
+writes, and ZEO is therefore better suited for read-intensive
+applications.  If every <tt class="class">ClientStorage</tt> is writing to the
+database all the time, this will result in a storm of invalidate
+messages being sent, and this might take up more processing time than
+the actual database operations themselves.<A NAME="tex2html2"
+  HREF="#foot429"><SUP>2</SUP></A>
+<P>
+On the other hand, for applications that have few writes in comparison
+to the number of read accesses, this aggressive caching can be a major
+win.  Consider a Slashdot-like discussion forum that divides the load
+among several Web servers.  If news items and postings are represented
+by objects and accessed through ZEO, then the most heavily accessed
+objects - the most recent or most popular postings - will very
+quickly wind up in the caches of the
+<tt class="class">ClientStorage</tt> instances on the front-end servers.  The
+back-end ZEO server will do relatively little work, only being called
+upon to return the occasional older posting that's requested, and to
+send the occasional invalidate message when a new posting is added.
+The ZEO server isn't going to be contacted for every single request,
+so its workload will remain manageable.
+
+<P>
+<BR><HR><H4>Footnotes</H4>
+<DL>
+<DT><A NAME="foot429">... themselves.</A><A NAME="foot429"
+ HREF="node22.html#tex2html2"><SUP>2</SUP></A>
+<DD>These messages are
+small and sent in batches, so there would need to be a lot of writes
+before it became a problem.
+
+</DL>
+<DIV CLASS="navigation">
+<p><hr>
+<table align="center" width="100%" cellpadding="0" cellspacing="2">
+<tr>
+<td><A href="zeo.html"><img src="/python/writing/icons/previous.gif"
+  border="0" height="32"
+  alt="Previous Page" width="32"></A></td>
+<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+  border="0" height="32"
+  alt="Up One Level" width="32"></A></td>
+<td><A HREF="node23.html"><img src="/python/writing/icons/next.gif"
+  border="0" height="32"
+  alt="Next Page" width="32"></A></td>
+<td align="center" width="100%">ZODB/ZEO Programming Guide</td>
+<td><A href="contents.html"><img src="/python/writing/icons/contents.gif"
+  border="0" height="32"
+  alt="Contents" width="32"></A></td>
+<td><img src="/python/writing/icons/blank.gif"
+  border="0" height="32"
+  alt="" width="32"></td>
+<td><img src="/python/writing/icons/blank.gif"
+  border="0" height="32"
+  alt="" width="32"></td>
+</tr></table>
+<b class="navlabel">Previous:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<hr>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
+</DIV>
+<!--End of Navigation Panel-->
+
+</BODY>
+</HTML>

doc/guide/zodb/node23.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.1 How ZEO Works</title>
-<META NAME="description" CONTENT="3.1 How ZEO Works">
+<title>3.2 Installing ZEO</title>
+<META NAME="description" CONTENT="3.2 Installing ZEO">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
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+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node24.html">
-<LINK REL="previous" href="zeo.html">
+<LINK REL="next" HREF="node26.html">
+<LINK REL="previous" HREF="node22.html">
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+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
 <tr>
-<td><A href="zeo.html"><img src="/python/writing/icons/previous.gif"
+<td><A HREF="node22.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
 <td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
@@ -40,83 +41,38 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node22.html">3.1 How ZEO Works</A>
 <b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node24.html">3.2.1 Requirements</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000410000000000000000">
-3.1 How ZEO Works</A>
+<H2><A NAME="SECTION000420000000000000000">
+3.2 Installing ZEO</A>
 </H2>
 
 <P>
-The ZODB, as I've described it so far, can only be used within a
-single Python process (though perhaps with multiple threads).  ZEO,
-Zope Enterprise Objects, extends the ZODB machinery to provide access
-to objects over a network.  The name "Zope Enterprise Objects" is a
-bit misleading; ZEO can be used to store Python objects and access
-them in a distributed fashion without Zope ever entering the picture.
-The combination of ZEO and ZODB is essentially a Python-specific
-object database.
-
-<P>
-ZEO consists of about 1400 lines of Python code.  The code is
-relatively small because it contains only code for a TCP/IP server,
-and for a new type of Storage, <tt class="class">ClientStorage</tt>.
-<tt class="class">ClientStorage</tt> doesn't use disk files at all; it simply
-makes remote procedure calls to the server, which then passes them on
-a regular <tt class="class">Storage</tt> class such as <tt class="class">FileStorage</tt>.  The
-following diagram lays out the system:
-
-<P>
-XXX insert diagram here later
+This section covers how to install the ZEO package, and how to 
+configure and run a ZEO Storage Server on a machine. 
 
 <P>
-Any number of processes can create a <tt class="class">ClientStorage</tt>
-instance, and any number of threads in each process can be using that
-instance.  <tt class="class">ClientStorage</tt> aggressively caches objects
-locally, so in order to avoid using stale data, the ZEO server sends
-an invalidate message to all the connected <tt class="class">ClientStorage</tt>
-instances on every write operation.  The invalidate message contains
-the object ID for each object that's been modified, letting the
-<tt class="class">ClientStorage</tt> instances delete the old data for the
-given object from their caches.
 
-<P>
-This design decision has some consequences you should be aware of.
-First, while ZEO isn't tied to Zope, it was first written for use with
-Zope, which stores HTML, images, and program code in the database.  As
-a result, reads from the database are <i>far</i> more frequent than
-writes, and ZEO is therefore better suited for read-intensive
-applications.  If every <tt class="class">ClientStorage</tt> is writing to the
-database all the time, this will result in a storm of invalidate
-messages being sent, and this might take up more processing time than
-the actual database operations themselves.
-
-<P>
-On the other hand, for applications that have few writes in comparison
-to the number of read accesses, this aggressive caching can be a major
-win.  Consider a Slashdot-like discussion forum that divides the load
-among several Web servers.  If news items and postings are represented
-by objects and accessed through ZEO, then the most heavily accessed
-objects - the most recent or most popular postings - will very
-quickly wind up in the caches of the
-<tt class="class">ClientStorage</tt> instances on the front-end servers.  The
-back-end ZEO server will do relatively little work, only being called
-upon to return the occasional older posting that's requested, and to
-send the occasional invalidate message when a new posting is added.
-The ZEO server isn't going to be contacted for every single request,
-so its workload will remain manageable.
+<p><hr>
+<!--Table of Child-Links-->
+<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
 
-<P>
+<UL>
+<LI><A href="node24.html">3.2.1 Requirements</a>
+<LI><A href="node25.html">3.2.2 Running a server</a>
+</ul>
+<!--End of Table of Child-Links-->
 
 <DIV CLASS="navigation">
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
 <tr>
-<td><A href="zeo.html"><img src="/python/writing/icons/previous.gif"
+<td><A HREF="node22.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
 <td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
@@ -136,11 +92,11 @@ so its workload will remain manageable.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node22.html">3.1 How ZEO Works</A>
 <b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node24.html">3.2.1 Requirements</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node24.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.2 Installing ZEO</title>
-<META NAME="description" CONTENT="3.2 Installing ZEO">
+<title>3.2.1 Requirements</title>
+<META NAME="description" CONTENT="3.2.1 Requirements">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node27.html">
+<LINK REL="next" HREF="node25.html">
 <LINK REL="previous" HREF="node23.html">
-<LINK REL="up" href="zeo.html">
+<LINK REL="up" HREF="node23.html">
 <LINK REL="next" HREF="node25.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node23.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node23.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node25.html"><img src="/python/writing/icons/next.gif"
@@ -40,33 +41,23 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node23.html">3.1 How ZEO Works</A>
-<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node25.html">3.2.1 Requirements</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node25.html">3.2.2 Running a server</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000420000000000000000">
-3.2 Installing ZEO</A>
-</H2>
+<H3><A NAME="SECTION000421000000000000000">
+3.2.1 Requirements</A>
+</H3>
 
 <P>
-This section covers how to install the ZEO package, and how to 
-configure and run a ZEO Storage Server on a machine. 
+The ZEO server software is included in ZODB3.  As with the rest of
+ZODB3, you'll need Python 2.1 or higher.
 
 <P>
 
-<p><hr>
-<!--Table of Child-Links-->
-<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
-
-<UL>
-<LI><A href="node25.html">3.2.1 Requirements</a>
-<LI><A href="node26.html">3.2.2 Installation</a>
-</ul>
-<!--End of Table of Child-Links-->
-
 <DIV CLASS="navigation">
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
@@ -74,7 +65,7 @@ configure and run a ZEO Storage Server on a machine.
 <td><A HREF="node23.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node23.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node25.html"><img src="/python/writing/icons/next.gif"
@@ -91,11 +82,11 @@ configure and run a ZEO Storage Server on a machine.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node23.html">3.1 How ZEO Works</A>
-<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node25.html">3.2.1 Requirements</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node25.html">3.2.2 Running a server</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node25.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.2.1 Requirements</title>
-<META NAME="description" CONTENT="3.2.1 Requirements">
+<title>3.2.2 Running a server</title>
+<META NAME="description" CONTENT="3.2.2 Running a server">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node26.html">
 <LINK REL="previous" HREF="node24.html">
-<LINK REL="up" HREF="node24.html">
+<LINK REL="up" HREF="node23.html">
 <LINK REL="next" HREF="node26.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +23,7 @@
 <td><A HREF="node24.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node24.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node23.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node26.html"><img src="/python/writing/icons/next.gif"
@@ -40,30 +40,23 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node26.html">3.2.2 Installation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node24.html">3.2.1 Requirements</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node26.html">3.3 Testing the ZEO</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H3><A NAME="SECTION000421000000000000000">
-3.2.1 Requirements</A>
+<H3><A NAME="SECTION000422000000000000000">
+3.2.2 Running a server</A>
 </H3>
 
 <P>
-To run a ZEO server, you'll need Python 1.5.2 or 2.0, and the ZODB
-packages from <a class="url" href="http://www.amk.ca/files/zodb/">http://www.amk.ca/files/zodb/</a>have to be installed.  
-
-<P>
-<i>Note for Python 1.5.2 users</i>: ZEO requires updated versions
-of the <tt class="module">asyncore.py</tt> and <tt class="module">asynchat.py</tt> modules that are
-included in 1.5.2's standard library.  Current versions of the ZODB
-distribution install private versions of these modules, so you
-shouldn't need to grab updated versions yourself.  (The symptom of
-this problem is a traceback on attempting to run a ZEO client program:
-the traceback is ``TypeError: too many arguments; expected 2, got 3''
-around line 100 of <span class="file">smac.py</span>.
+The start.py script in the ZEO directory can be used to start a
+server.  Run it with the -h option to see the various values.  If
+you're just experimenting, a good choise is to use 
+<code>python ZEO/start.py -D -U /tmp/zeosocket</code> to run ZEO in
+debug mode and with a Unix domain socket.
 
 <P>
 
@@ -74,7 +67,7 @@ around line 100 of <span class="file">smac.py</span>.
 <td><A HREF="node24.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node24.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node23.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node26.html"><img src="/python/writing/icons/next.gif"
@@ -91,11 +84,11 @@ around line 100 of <span class="file">smac.py</span>.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node26.html">3.2.2 Installation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node24.html">3.2.1 Requirements</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node23.html">3.2 Installing ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node26.html">3.3 Testing the ZEO</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node26.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.2.2 Installation</title>
-<META NAME="description" CONTENT="3.2.2 Installation">
+<title>3.3 Testing the ZEO Installation</title>
+<META NAME="description" CONTENT="3.3 Testing the ZEO Installation">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="previous" HREF="node25.html">
-<LINK REL="up" HREF="node24.html">
 <LINK REL="next" HREF="node27.html">
+<LINK REL="previous" HREF="node23.html">
+<LINK REL="up" href="zeo.html">
+<LINK REL="next" HREF="node27.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -22,7 +24,7 @@
 <td><A HREF="node25.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node24.html"><img src="/python/writing/icons/up.gif"
+<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node27.html"><img src="/python/writing/icons/next.gif"
@@ -39,24 +41,54 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node25.html">3.2.1 Requirements</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node27.html">3.3 Configuring and Running</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node25.html">3.2.2 Running a server</A>
+<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node27.html">3.4 ZEO Programming Notes</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H3><A NAME="SECTION000422000000000000000">
-3.2.2 Installation</A>
-</H3>
+<H2><A NAME="SECTION000430000000000000000">
+3.3 Testing the ZEO Installation</A>
+</H2>
+
+<P>
+Once a ZEO server is up and running, using it is just like using ZODB
+with a more conventional disk-based storage; no new programming
+details are introduced by using a remote server.  The only difference
+is that programs must create a <tt class="class">ClientStorage</tt> instance instead
+of a <tt class="class">FileStorage</tt> instance.  From that point onward, ZODB-based
+code is happily unaware that objects are being retrieved from a ZEO
+server, and not from the local disk.
+
+<P>
+As an example, and to test whether ZEO is working correctly, try
+running the following lines of code, which will connect to the server,
+add some bits of data to the root of the ZODB, and commits the
+transaction:
+
+<P>
+<div class="verbatim"><pre>
+from ZEO import ClientStorage
+from ZODB import DB
+
+# Change next line to connect to your ZEO server
+addr = ('kronos.example.com', 1975)
+storage = ClientStorage.ClientStorage(addr)
+db = DB(storage)
+conn = db.open()
+root = conn.root()
+
+# Store some things in the root
+root['list'] = ['a', 'b', 1.0, 3]
+root['dict'] = {'a':1, 'b':4}
+
+# Commit the transaction
+get_transaction().commit()
+</pre></div>
 
 <P>
-Installing the ZEO package is easy.  Just run <code>python setup.py
-install</code>.  This will install the ZEO/ package into your Python
-installation, and copy various files into their proper locations:
-<span class="file">zeo.conf</span> will be put into <span class="file">/usr/local/etc/</span>, a <span class="file">zeo</span> startup
-script will be put in <span class="file">/etc/rc.d/init.d/</span>, and the <span class="file">zeod</span>
-daemon program will be placed in <span class="file">/usr/local/bin</span>.
+If this code runs properly, then your ZEO server is working correctly.
 
 <P>
 
@@ -67,7 +99,7 @@ daemon program will be placed in <span class="file">/usr/local/bin</span>.
 <td><A HREF="node25.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node24.html"><img src="/python/writing/icons/up.gif"
+<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node27.html"><img src="/python/writing/icons/next.gif"
@@ -84,11 +116,11 @@ daemon program will be placed in <span class="file">/usr/local/bin</span>.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node25.html">3.2.1 Requirements</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node24.html">3.2 Installing ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node27.html">3.3 Configuring and Running</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node25.html">3.2.2 Running a server</A>
+<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node27.html">3.4 ZEO Programming Notes</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node27.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.3 Configuring and Running a ZEO Server</title>
-<META NAME="description" CONTENT="3.3 Configuring and Running a ZEO Server">
+<title>3.4 ZEO Programming Notes</title>
+<META NAME="description" CONTENT="3.4 ZEO Programming Notes">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
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+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node28.html">
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+<LINK REL="previous" HREF="node26.html">
 <LINK REL="up" href="zeo.html">
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+<meta name='aesop' content='information'>
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 <body>
 <DIV CLASS="navigation">
@@ -40,23 +41,27 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node26.html">3.2.2 Installation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node26.html">3.3 Testing the ZEO</A>
 <b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node28.html">3.4 Testing the ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node28.html">3.5 Sample Application: chatter.py</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000430000000000000000">
-3.3 Configuring and Running a ZEO Server</A>
+<H2><A NAME="SECTION000440000000000000000">
+3.4 ZEO Programming Notes</A>
 </H2>
 
 <P>
-Edit <code>/usr/local/etc/zeo.conf</code> appropriately for your desired
-setup.  This configuration file controls the port on which ZEO will
-listen for connections, the user and group IDs under which the server
-will be executed, and the location of the concrete <tt class="class">Storage</tt>
-object that will be made network-accessible.
+ZEO is written using <tt class="module">asyncore</tt>, from the Python standard
+library.  It assumes that some part of the user application is running
+an <tt class="module">asyncore</tt> mainloop.  For example, Zope run the loop in a
+separate thread and ZEO uses that.  If your application does not have
+a mainloop, ZEO will not process incoming invalidation messages until
+you make some call into ZEO.  The <tt class="method">Connection.sync</tt> method can
+be used to process pending invalidation messages.  You can call it
+when you want to make sure the <tt class="class">Connection</tt> has the most recent
+version of every object, but you don't have any other work for ZEO to do.
 
 <P>
 
@@ -84,11 +89,11 @@ object that will be made network-accessible.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node26.html">3.2.2 Installation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node26.html">3.3 Testing the ZEO</A>
 <b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node28.html">3.4 Testing the ZEO</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node28.html">3.5 Sample Application: chatter.py</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node28.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.4 Testing the ZEO Installation</title>
-<META NAME="description" CONTENT="3.4 Testing the ZEO Installation">
+<title>3.5 Sample Application: chatter.py</title>
+<META NAME="description" CONTENT="3.5 Sample Application: chatter.py">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node29.html">
 <LINK REL="previous" HREF="node27.html">
 <LINK REL="up" href="zeo.html">
 <LINK REL="next" HREF="node29.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -40,54 +40,154 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node27.html">3.3 Configuring and Running</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node27.html">3.4 ZEO Programming Notes</A>
 <b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node29.html">3.5 ZEO Programming Notes</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000440000000000000000">
-3.4 Testing the ZEO Installation</A>
+<H2><A NAME="SECTION000450000000000000000">
+3.5 Sample Application: chatter.py</A>
 </H2>
 
 <P>
-Once a ZEO server is up and running, using it is just like using ZODB
-with a more conventional disk-based storage; no new programming
-details are introduced by using a remote server.  The only difference
-is that programs must create a <tt class="class">ClientStorage</tt> instance instead
-of a <tt class="class">FileStorage</tt> instance.  From that point onward, ZODB-based
-code is happily unaware that objects are being retrieved from a ZEO
-server, and not from the local disk.
+For an example application, we'll build a little chat application.
+What's interesting is that none of the application's code deals with
+network programming at all; instead, an object will hold chat
+messages, and be magically shared between all the clients through ZEO.
+I won't present the complete script here; it's included in my ZODB
+distribution, and you can download it from
+<a class="url" href="http://www.amk.ca/zodb/demos/">http://www.amk.ca/zodb/demos/</a>.  Only the interesting portions of
+the code will be covered here.
+
+<P>
+The basic data structure is the <tt class="class">ChatSession</tt> object,
+which provides an <tt class="method">add_message()</tt> method that adds a
+message, and a <tt class="method">new_messages()</tt> method that returns a list
+of new messages that have accumulated since the last call to
+<tt class="method">new_messages()</tt>.  Internally, <tt class="class">ChatSession</tt>
+maintains a B-tree that uses the time as the key, and stores the
+message as the corresponding value.
+
+<P>
+The constructor for <tt class="class">ChatSession</tt> is pretty simple; it simply
+creates an attribute containing a B-tree:
+
+<P>
+<div class="verbatim"><pre>
+class ChatSession(Persistent):
+    def __init__(self, name):
+        self.name = name
+        # Internal attribute: _messages holds all the chat messages.        
+        self._messages = BTrees.OOBTree.OOBTree()
+</pre></div>
+
+<P>
+<tt class="method">add_message()</tt> has to add a message to the
+<code>_messages</code> B-tree.  A complication is that it's possible
+that some other client is trying to add a message at the same time;
+when this happens, the client that commits first wins, and the second
+client will get a <tt class="exception">ConflictError</tt> exception when it tries to
+commit.  For this application, <tt class="exception">ConflictError</tt> isn't serious
+but simply means that the operation has to be retried; other
+applications might treat it as a fatal error.  The code uses
+<code>try...except...else</code> inside a <code>while</code> loop,
+breaking out of the loop when the commit works without raising an
+exception.
+
+<P>
+<div class="verbatim"><pre>
+    def add_message(self, message):
+        """Add a message to the channel.
+        message -- text of the message to be added
+        """
+
+        while 1:
+            try:
+                now = time.time()
+                self._messages[now] = message
+                get_transaction().commit()
+            except ConflictError:
+                # Conflict occurred; this process should pause and
+                # wait for a little bit, then try again.
+                time.sleep(.2)
+                pass
+            else:
+                # No ConflictError exception raised, so break
+                # out of the enclosing while loop.
+                break
+        # end while
+</pre></div>
+
+<P>
+<tt class="method">new_messages()</tt> introduces the use of <i>volatile</i>
+attributes.  Attributes of a persistent object that begin with
+<code>_v_</code> are considered volatile and are never stored in the
+database.  <tt class="method">new_messages()</tt> needs to store the last time
+the method was called, but if the time was stored as a regular
+attribute, its value would be committed to the database and shared
+with all the other clients.  <tt class="method">new_messages()</tt> would then
+return the new messages accumulated since any other client called
+<tt class="method">new_messages()</tt>, which isn't what we want.
+
+<P>
+<div class="verbatim"><pre>
+    def new_messages(self):
+        "Return new messages."
+
+        # self._v_last_time is the time of the most recent message
+        # returned to the user of this class. 
+        if not hasattr(self, '_v_last_time'):
+            self._v_last_time = 0
+
+        new = []
+        T = self._v_last_time
+
+        for T2, message in self._messages.items():
+            if T2 &gt; T:
+                new.append(message)
+                self._v_last_time = T2
+
+        return new
+</pre></div>
 
 <P>
-As an example, and to test whether ZEO is working correctly, try
-running the following lines of code, which will connect to the server,
-add some bits of data to the root of the ZODB, and commits the
-transaction:
+This application is interesting because it uses ZEO to easily share a
+data structure; ZEO and ZODB are being used for their networking
+ability, not primarily for their data storage ability.  I can foresee
+many interesting applications using ZEO in this way:
 
 <P>
-<dl><dd><pre class="verbatim">
-from ZEO import ClientStorage
-from ZODB import DB
 
-# Change next line to connect to your ZEO server
-addr = ('kronos.example.com', 1975)
-storage = ClientStorage.ClientStorage(addr)
-db = DB(storage)
-conn = db.open()
-root = conn.root()
+<UL>
+<LI>With a Tkinter front-end, and a cleverer, more scalable data
+  structure, you could build a shared whiteboard using the same
+  technique.
+
+<P>
+</LI>
+<LI>A shared chessboard object would make writing a networked chess
+  game easy.  
 
-# Store some things in the root
-root['list'] = ['a', 'b', 1.0, 3]
-root['dict'] = {'a':1, 'b':4}
+<P>
+</LI>
+<LI>You could create a Python class containing a CD's title and
+  track information.  To make a CD database, a read-only ZEO server
+  could be opened to the world, or an HTTP or XML-RPC interface could
+  be written on top of the ZODB.
 
-# Commit the transaction
-get_transaction().commit()
-</pre></dl>
+<P>
+</LI>
+<LI>A program like Quicken could use a ZODB on the local disk to
+  store its data.  This avoids the need to write and maintain
+  specialized I/O code that reads in your objects and writes them out;
+  instead you can concentrate on the problem domain, writing objects
+  that represent cheques, stock portfolios, or whatever.
 
 <P>
-If this code runs properly, then your ZEO server is working correctly.
+</LI>
+</UL>
 
 <P>
 
@@ -115,11 +215,11 @@ If this code runs properly, then your ZEO server is working correctly.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node27.html">3.3 Configuring and Running</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node27.html">3.4 ZEO Programming Notes</A>
 <b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node29.html">3.5 ZEO Programming Notes</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node29.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.5 ZEO Programming Notes</title>
-<META NAME="description" CONTENT="3.5 ZEO Programming Notes">
+<title>4 Transactions and Versioning</title>
+<META NAME="description" CONTENT="4 Transactions and Versioning">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
+<LINK REL="next" HREF="node34.html">
+<LINK REL="previous" href="zeo.html">
+<LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node30.html">
-<LINK REL="previous" HREF="node28.html">
-<LINK REL="up" href="zeo.html">
-<LINK REL="next" HREF="node30.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node28.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node30.html"><img src="/python/writing/icons/next.gif"
@@ -40,21 +41,30 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node28.html">3.4 Testing the ZEO</A>
-<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node30.html">3.6 Sample Application: chatter.py</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node28.html">3.5 Sample Application: chatter.py</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node30.html">4.1 Subtransactions</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000450000000000000000">
-3.5 ZEO Programming Notes</A>
-</H2>
+<H1><A NAME="SECTION000500000000000000000">
+4 Transactions and Versioning</A>
+</H1>
 
 <P>
-XXX The Connection.sync() method and its necessity (if it works at all!) 
 
-<P>
+<p><hr>
+<!--Table of Child-Links-->
+<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
+
+<UL>
+<LI><A href="node30.html">4.1 Subtransactions</a>
+<LI><A href="node31.html">4.2 Undoing Changes</a>
+<LI><A href="node32.html">4.3 Versions</a>
+<LI><A href="node33.html">4.4 Multithreaded ZODB Programs</a>
+</ul>
+<!--End of Table of Child-Links-->
 
 <DIV CLASS="navigation">
 <p><hr>
@@ -63,7 +73,7 @@ XXX The Connection.sync() method and its necessity (if it works at all!)
 <td><A HREF="node28.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node30.html"><img src="/python/writing/icons/next.gif"
@@ -80,11 +90,11 @@ XXX The Connection.sync() method and its necessity (if it works at all!)
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node28.html">3.4 Testing the ZEO</A>
-<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node30.html">3.6 Sample Application: chatter.py</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node28.html">3.5 Sample Application: chatter.py</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node30.html">4.1 Subtransactions</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node3.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node2.html">
 <LINK REL="up" HREF="node2.html">
 <LINK REL="next" HREF="node4.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -106,7 +107,7 @@ accessed in a while.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node2.html">1 Introduction</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node4.html">1.2 OODBs vs. Relational</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node30.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>3.6 Sample Application: chatter.py</title>
-<META NAME="description" CONTENT="3.6 Sample Application: chatter.py">
+<title>4.1 Subtransactions</title>
+<META NAME="description" CONTENT="4.1 Subtransactions">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
+<LINK REL="next" HREF="node31.html">
 <LINK REL="previous" HREF="node29.html">
-<LINK REL="up" href="zeo.html">
+<LINK REL="up" HREF="node29.html">
 <LINK REL="next" HREF="node31.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -22,7 +24,7 @@
 <td><A HREF="node29.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node31.html"><img src="/python/writing/icons/next.gif"
@@ -39,154 +41,52 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node29.html">3.5 ZEO Programming Notes</A>
-<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node31.html">4.2 Undoing Changes</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000460000000000000000">
-3.6 Sample Application: chatter.py</A>
+<H2><A NAME="SECTION000510000000000000000">
+4.1 Subtransactions</A>
 </H2>
 
 <P>
-For an example application, we'll build a little chat application.
-What's interesting is that none of the application's code deals with
-network programming at all; instead, an object will hold chat
-messages, and be magically shared between all the clients through ZEO.
-I won't present the complete script here; it's included in my ZODB
-distribution, and you can download it from
-<a class="url" href="http://www.amk.ca/zodb/demos/">http://www.amk.ca/zodb/demos/</a>.  Only the interesting portions of
-the code will be covered here.
-
-<P>
-The basic data structure is the <tt class="class">ChatSession</tt> object,
-which provides an <tt class="method">add_message()</tt> method that adds a
-message, and a <tt class="method">new_messages()</tt> method that returns a list
-of new messages that have accumulated since the last call to
-<tt class="method">new_messages()</tt>.  Internally, <tt class="class">ChatSession</tt>
-maintains a B-tree that uses the time as the key, and stores the
-message as the corresponding value.
-
-<P>
-The constructor for <tt class="class">ChatSession</tt> is pretty simple; it simply
-creates an attribute containing a B-tree:
-
-<P>
-<dl><dd><pre class="verbatim">
-class ChatSession(Persistent):
-    def __init__(self, name):
-        self.name = name
-        # Internal attribute: _messages holds all the chat messages.        
-        self._messages = BTree.BTree()
-</pre></dl>
-
-<P>
-<tt class="method">add_message()</tt> has to add a message to the
-<code>_messages</code> B-tree.  A complication is that it's possible
-that some other client is trying to add a message at the same time;
-when this happens, the client that commits first wins, and the second
-client will get a <tt class="exception">ConflictError</tt> exception when it tries to
-commit.  For this application, <tt class="exception">ConflictError</tt> isn't serious
-but simply means that the operation has to be retried; other
-applications might treat it as a fatal error.  The code uses
-<code>try...except...else</code> inside a <code>while</code> loop,
-breaking out of the loop when the commit works without raising an
-exception.
-
-<P>
-<dl><dd><pre class="verbatim">
-    def add_message(self, message):
-        """Add a message to the channel.
-        message -- text of the message to be added
-        """
-
-        while 1:
-            try:
-                now = time.time()
-                self._messages[now] = message
-                get_transaction().commit()
-            except ConflictError:
-                # Conflict occurred; this process should pause and
-                # wait for a little bit, then try again.
-                time.sleep(.2)
-                pass
-            else:
-                # No ConflictError exception raised, so break
-                # out of the enclosing while loop.
-                break
-        # end while
-</pre></dl>
-
-<P>
-<tt class="method">new_messages()</tt> introduces the use of <i>volatile</i>
-attributes.  Attributes of a persistent object that begin with
-<code>_v_</code> are considered volatile and are never stored in the
-database.  <tt class="method">new_messages()</tt> needs to store the last time
-the method was called, but if the time was stored as a regular
-attribute, its value would be committed to the database and shared
-with all the other clients.  <tt class="method">new_messages()</tt> would then
-return the new messages accumulated since any other client called
-<tt class="method">new_messages()</tt>, which isn't what we want.
-
-<P>
-<dl><dd><pre class="verbatim">
-    def new_messages(self):
-        "Return new messages."
-
-        # self._v_last_time is the time of the most recent message
-        # returned to the user of this class. 
-        if not hasattr(self, '_v_last_time'):
-            self._v_last_time = 0
-
-        new = []
-        T = self._v_last_time
-
-        for T2, message in self._messages.items():
-            if T2 &gt; T:
-                new.append(message)
-                self._v_last_time = T2
-
-        return new
-</pre></dl>
-
-<P>
-This application is interesting because it uses ZEO to easily share a
-data structure; ZEO and ZODB are being used for their networking
-ability, not primarily for their data storage ability.  I can foresee
-many interesting applications using ZEO in this way:
+Subtransactions can be created within a transaction.  Each
+subtransaction can be individually committed and aborted, but the
+changes within a subtransaction are not truly committed until the
+containing transaction is committed.
 
 <P>
-
-<UL>
-<LI>With a Tkinter front-end, and a cleverer, more scalable data
-  structure, you could build a shared whiteboard using the same
-  technique.
+The primary purpose of subtransactions is to decrease the memory usage
+of transactions that touch a very large number of objects.  Consider a
+transaction during which 200,000 objects are modified.  All the
+objects that are modified in a single transaction have to remain in
+memory until the transaction is committed, because the ZODB can't
+discard them from the object cache.  This can potentially make the
+memory usage quite large.  With subtransactions, a commit can be be
+performed at intervals, say, every 10,000 objects.  Those 10,000
+objects are then written to permanent storage and can be purged from
+the cache to free more space.
 
 <P>
-</LI>
-<LI>A shared chessboard object would make writing a networked chess
-  game easy.  
+To commit a subtransaction instead of a full transaction, 
+pass a true value to the <tt class="method">commit()</tt>
+or <tt class="method">abort()</tt> method of the <tt class="class">Transaction</tt> object.
 
 <P>
-</LI>
-<LI>You could create a Python class containing a CD's title and
-  track information.  To make a CD database, a read-only ZEO server
-  could be opened to the world, or an HTTP or XML-RPC interface could
-  be written on top of the ZODB.
+<div class="verbatim"><pre>
+# Commit a subtransaction
+get_transaction().commit(1)     
 
-<P>
-</LI>
-<LI>A program like Quicken could use a ZODB on the local disk to
-  store its data.  This avoids the need to write and maintain
-  specialized I/O code that reads in your objects and writes them out;
-  instead you can concentrate on the problem domain, writing objects
-  that represent cheques, stock portfolios, or whatever.
+# Abort a subtransaction
+get_transaction().abort(1)
+</pre></div>
 
 <P>
-</LI>
-</UL>
+A new subtransaction is automatically started on committing or
+aborting the previous subtransaction.
 
 <P>
 
@@ -197,7 +97,7 @@ many interesting applications using ZEO in this way:
 <td><A HREF="node29.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A href="zeo.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node31.html"><img src="/python/writing/icons/next.gif"
@@ -214,11 +114,11 @@ many interesting applications using ZEO in this way:
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node29.html">3.5 ZEO Programming Notes</A>
-<b class="navlabel">Up:</b> <a class="sectref" href="zeo.html">3 ZEO</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node31.html">4.2 Undoing Changes</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node31.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>4 Transactions and Versioning</title>
-<META NAME="description" CONTENT="4 Transactions and Versioning">
+<title>4.2 Undoing Changes</title>
+<META NAME="description" CONTENT="4.2 Undoing Changes">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node36.html">
-<LINK REL="previous" href="zeo.html">
-<LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node32.html">
+<LINK REL="previous" HREF="node30.html">
+<LINK REL="up" HREF="node29.html">
+<LINK REL="next" HREF="node32.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node30.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node32.html"><img src="/python/writing/icons/next.gif"
@@ -40,31 +41,99 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node30.html">3.6 Sample Application: chatter.py</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node32.html">4.1 Subtransactions</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node30.html">4.1 Subtransactions</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node32.html">4.3 Versions</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H1><A NAME="SECTION000500000000000000000">
-4 Transactions and Versioning</A>
-</H1>
+<H2><A NAME="SECTION000520000000000000000">
+4.2 Undoing Changes</A>
+</H2>
 
 <P>
+Some types of <tt class="class">Storage</tt> support undoing a transaction even after
+it's been committed.  You can tell if this is the case by calling the
+<tt class="method">supportsUndo()</tt> method of the <tt class="class">DB</tt> instance, which
+returns true if the underlying storage supports undo.  Alternatively
+you can call the <tt class="method">supportsUndo()</tt> method on the underlying
+storage instance.
 
-<p><hr>
-<!--Table of Child-Links-->
-<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
+<P>
+If a database supports undo, then the <tt class="method">undoLog(<var>start</var>,
+<var>end</var><big>[</big>, func<big>]</big>)</tt> method on the <tt class="class">DB</tt> instance returns
+the log of past transactions, returning transactions between the times
+<var>start</var> and <var>end</var>, measured in seconds from the epoch.   
+If present, <var>func</var> is a function that acts as a filter on the
+transactions to be returned; it's passed a dictionary representing
+each transaction, and only transactions for which <var>func</var> returns
+true will be included in the list of transactions returned to the
+caller of <tt class="method">undoLog()</tt>.  The dictionary contains keys for
+various properties of the transaction.  The most important keys are
+"<tt class="samp">id</tt>", for the transaction ID, and "<tt class="samp">time</tt>", for the time at
+which the transaction was committed.  
+
+<P>
+<div class="verbatim"><pre>
+&gt;&gt;&gt; print storage.undoLog(0, sys.maxint)
+[{'description': '',
+  'id': 'AzpGEGqU/0QAAAAAAAAGMA',
+  'time': 981126744.98,
+  'user_name': ''},
+ {'description': '',
+  'id': 'AzpGC/hUOKoAAAAAAAAFDQ',
+  'time': 981126478.202,
+  'user_name': ''}
+  ...
+</pre></div>
+
+<P>
+To store a description and a user name on a commit, get the current
+transaction and call the <tt class="method">note(<var>text</var>)</tt> method to store a
+description, and the
+<tt class="method">setUser(<var>user_name</var>)</tt> method to store the user name.  
+While <tt class="method">setUser()</tt> overwrites the current user name and replaces
+it with the new value, the <tt class="method">note()</tt> method always adds the text
+to the transaction's description, so it can be called several times to
+log several different changes made in the course of a single
+transaction.
 
-<UL>
-<LI><A href="node32.html">4.1 Subtransactions</a>
-<LI><A href="node33.html">4.2 Undoing Changes</a>
-<LI><A href="node34.html">4.3 Versions</a>
-<LI><A href="node35.html">4.4 Multithreaded ZODB Programs</a>
-</ul>
-<!--End of Table of Child-Links-->
+<P>
+<div class="verbatim"><pre>
+get_transaction().setUser('amk')
+get_transaction().note('Change ownership')
+</pre></div>
+
+<P>
+To undo a transaction, call the <tt class="method">DB.undo(<var>id</var>)</tt> method,
+passing it the ID of the transaction to undo.  If the transaction
+can't be undone, a <tt class="exception">ZODB.POSException.UndoError</tt> exception
+will be raised, with the message ``non-undoable
+transaction''.  Usually this will happen because later transactions
+modified the objects affected by the transaction you're trying to
+undo.
+
+<P>
+After you call <tt class="method">undo()</tt> you must commit the transaction for the
+undo to actually be applied.
+<A NAME="tex2html3"
+  HREF="#foot583"><SUP>3</SUP></A>  There is one glitch in the undo process.  The thread
+that calls undo may not see the changes to the object until it calls
+<tt class="method">Connection.sync()</tt> or commits another transaction.
+
+<P>
+<BR><HR><H4>Footnotes</H4>
+<DL>
+<DT><A NAME="foot583">... applied.</A><A NAME="foot583"
+ HREF="node31.html#tex2html3"><SUP>3</SUP></A>
+<DD>There are actually two different ways a storage can
+implement the undo feature.  Most of the storages that ship with ZODB
+use the transactional form of undo described in the main text.  Some
+storages may use a non-transactional undo makes changes visible
+immediately.
 
+</DL>
 <DIV CLASS="navigation">
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
@@ -72,7 +141,7 @@
 <td><A HREF="node30.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node32.html"><img src="/python/writing/icons/next.gif"
@@ -89,11 +158,11 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node30.html">3.6 Sample Application: chatter.py</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node32.html">4.1 Subtransactions</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node30.html">4.1 Subtransactions</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node32.html">4.3 Versions</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node32.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>4.1 Subtransactions</title>
-<META NAME="description" CONTENT="4.1 Subtransactions">
+<title>4.3 Versions</title>
+<META NAME="description" CONTENT="4.3 Versions">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node33.html">
 <LINK REL="previous" HREF="node31.html">
-<LINK REL="up" HREF="node31.html">
+<LINK REL="up" HREF="node29.html">
 <LINK REL="next" HREF="node33.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node31.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node33.html"><img src="/python/writing/icons/next.gif"
@@ -40,52 +41,73 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node33.html">4.2 Undoing Changes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node31.html">4.2 Undoing Changes</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node33.html">4.4 Multithreaded ZODB Programs</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000510000000000000000">
-4.1 Subtransactions</A>
+<H2><A NAME="SECTION000530000000000000000">
+4.3 Versions</A>
 </H2>
 
 <P>
-Subtransactions can be created within a transaction.  Each
-subtransaction can be individually committed and aborted, but the
-changes within a subtransaction are not truly committed until the
-containing transaction is committed.
+While many subtransactions can be contained within a single regular
+transaction, it's also possible to contain many regular transactions
+within a long-running transaction, called a version in ZODB
+terminology.  Inside a version, any number of transactions can be
+created and committed or rolled back, but the changes within a version
+are not made visible to other connections to the same ZODB.
 
 <P>
-The primary purpose of subtransactions is to decrease the memory usage
-of transactions that touch a very large number of objects.  Consider a
-transaction during which 200,000 objects are modified.  All the
-objects that are modified in a single transaction have to remain in
-memory until the transaction is committed, because the ZODB can't
-discard them from the object cache.  This can potentially make the
-memory usage quite large.  With subtransactions, a commit can be be
-performed at intervals, say, every 10,000 objects.  Those 10,000
-objects are then written to permanent storage and can be purged from
-the cache to free more space.
+Not all storages support versions, but you can test for versioning
+ability by calling <tt class="method">supportsVersions()</tt> method of the
+<tt class="class">DB</tt> instance, which returns true if the underlying storage
+supports versioning.
 
 <P>
-To commit a subtransaction instead of a full transaction, 
-pass a true value to the <tt class="method">commit()</tt>
-or <tt class="method">abort()</tt> method of the <tt class="class">Transaction</tt> object.
+A version can be selected when creating the <tt class="class">Connection</tt>
+instance using the <tt class="method">DB.open(<big>[</big><var>version</var><big>]</big>)</tt> method.
+The <var>version</var> argument must be a string that will be used as the
+name of the version.
 
 <P>
-<dl><dd><pre class="verbatim">
-# Commit a subtransaction
-get_transaction().commit(1)	
+<div class="verbatim"><pre>
+vers_conn = db.open(version='Working version')
+</pre></div>
 
-# Abort a subtransaction
-get_transaction().abort(1)
-</pre></dl>
+<P>
+Transactions can then be committed and aborted using this versioned
+connection.  Other connections that don't specify a version, or
+provide a different version name, will not see changes committed
+within the version named "<tt class="samp">Working&nbsp;version</tt>".  To commit or abort a
+version, which will either make the changes visible to all clients or
+roll them back, call the <tt class="method">DB.commitVersion()</tt> or
+<tt class="method">DB.abortVersion()</tt> methods.
+XXX what are the source and dest arguments for?
+
+<P>
+The ZODB makes no attempt to reconcile changes between different
+versions.  Instead, the first version which modifies an object will
+gain a lock on that object.  Attempting to modify the object from a
+different version or from an unversioned connection will cause a
+<tt class="exception">ZODB.POSException.VersionLockError</tt> to be raised:
+
+<P>
+<div class="verbatim"><pre>
+from ZODB.POSException import VersionLockError
+
+try:
+    get_transaction().commit()
+except VersionLockError, (obj_id, version):
+    print ('Cannot commit; object %s '
+           'locked by version %s' % (obj_id, version))
+</pre></div>
 
 <P>
-A new subtransaction is automatically started on committing or
-aborting the previous subtransaction.
+The exception provides the ID of the locked object, and the name of
+the version having a lock on it.
 
 <P>
 
@@ -96,7 +118,7 @@ aborting the previous subtransaction.
 <td><A HREF="node31.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node33.html"><img src="/python/writing/icons/next.gif"
@@ -113,11 +135,11 @@ aborting the previous subtransaction.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node33.html">4.2 Undoing Changes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node31.html">4.2 Undoing Changes</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node33.html">4.4 Multithreaded ZODB Programs</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node33.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>4.2 Undoing Changes</title>
-<META NAME="description" CONTENT="4.2 Undoing Changes">
+<title>4.4 Multithreaded ZODB Programs</title>
+<META NAME="description" CONTENT="4.4 Multithreaded ZODB Programs">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node34.html">
 <LINK REL="previous" HREF="node32.html">
-<LINK REL="up" HREF="node31.html">
+<LINK REL="up" HREF="node29.html">
 <LINK REL="next" HREF="node34.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +23,7 @@
 <td><A HREF="node32.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node34.html"><img src="/python/writing/icons/next.gif"
@@ -40,78 +40,22 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node32.html">4.1 Subtransactions</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node34.html">4.3 Versions</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node32.html">4.3 Versions</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000520000000000000000">
-4.2 Undoing Changes</A>
+<H2><A NAME="SECTION000540000000000000000">
+4.4 Multithreaded ZODB Programs</A>
 </H2>
 
 <P>
-Some types of <tt class="class">Storage</tt> support undoing a transaction even after
-it's been committed.  You can tell if this is the case by calling the
-<tt class="method">supportsUndo()</tt> method of the <tt class="class">DB</tt> instance, which
-returns true if the underlying storage supports undo.  Alternatively
-you can call the <tt class="method">supportsUndo()</tt> method on the underlying
-storage instance.
-
-<P>
-If a database supports undo, then the <tt class="method">undoLog(<var>start</var>,
-<var>end</var><big>[</big>, func<big>]</big>)</tt> method on the <tt class="class">DB</tt> instance returns
-the log of past transactions, returning transactions between the times
-<var>start</var> and <var>end</var>, measured in seconds from the epoch.   
-If present, <var>func</var> is a function that acts as a filter on the
-transactions to be returned; it's passed a dictionary representing
-each transaction, and only transactions for which <var>func</var> returns
-true will be included in the list of transactions returned to the
-caller of <tt class="method">undoLog()</tt>.  The dictionary contains keys for
-various properties of the transaction.  The most important keys are
-"<tt class="samp">id</tt>", for the transaction ID, and "<tt class="samp">time</tt>", for the time at
-which the transaction was committed.  
-
-<P>
-<dl><dd><pre class="verbatim">
-&gt;&gt;&gt; print storage.undoLog(0, sys.maxint)
-[{'description': '',
-  'id': 'AzpGEGqU/0QAAAAAAAAGMA',
-  'time': 981126744.98,
-  'user_name': ''},
- {'description': '',
-  'id': 'AzpGC/hUOKoAAAAAAAAFDQ',
-  'time': 981126478.202,
-  'user_name': ''}
-  ...
-</pre></dl>
-
-<P>
-To store a description and a user name on a commit, get the current
-transaction and call the <tt class="method">note(<var>text</var>)</tt> method to store a
-description, and the
-<tt class="method">setUser(<var>user_name</var>)</tt> method to store the user name.  
-While <tt class="method">setUser()</tt> overwrites the current user name and replaces
-it with the new value, the <tt class="method">note()</tt> method always adds the text
-to the transaction's description, so it can be called several times to
-log several different changes made in the course of a single
-transaction.
-
-<P>
-<dl><dd><pre class="verbatim">
-get_transaction().setUser('amk')
-get_transaction().note('Change ownership')
-</pre></dl>
-
-<P>
-To undo a transaction, call the <tt class="method">DB.undo(<var>id</var>)</tt> method,
-passing it the ID of the transaction to undo.  If the transaction
-can't be undone, a <tt class="exception">ZODB.POSException.UndoError</tt> exception
-will be raised, with the message ``non-undoable
-transaction''.  Usually this will happen because later transactions
-modified the objects affected by the transaction you're trying to
-undo.
+ZODB databases can be accessed from multithreaded Python programs.
+The <tt class="class">Storage</tt> and <tt class="class">DB</tt> instances can be shared among
+several threads, as long as individual <tt class="class">Connection</tt> instances
+are created for each thread.  
 
 <P>
 
@@ -122,7 +66,7 @@ undo.
 <td><A HREF="node32.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node29.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node34.html"><img src="/python/writing/icons/next.gif"
@@ -139,11 +83,11 @@ undo.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node32.html">4.1 Subtransactions</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node34.html">4.3 Versions</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node32.html">4.3 Versions</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node29.html">4 Transactions and Versioning</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node34.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>4.3 Versions</title>
-<META NAME="description" CONTENT="4.3 Versions">
+<title>5 Related Modules</title>
+<META NAME="description" CONTENT="5 Related Modules">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
+<LINK REL="next" HREF="node38.html">
+<LINK REL="previous" HREF="node29.html">
+<LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node35.html">
-<LINK REL="previous" HREF="node33.html">
-<LINK REL="up" HREF="node31.html">
-<LINK REL="next" HREF="node35.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node33.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node35.html"><img src="/python/writing/icons/next.gif"
@@ -40,75 +41,33 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node33.html">4.2 Undoing Changes</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node35.html">4.4 Multithreaded ZODB Programs</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node33.html">4.4 Multithreaded ZODB Programs</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node35.html">5.1 ZODB.PersistentMapping</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000530000000000000000">
-4.3 Versions</A>
-</H2>
-
-<P>
-While many subtransactions can be contained within a single regular
-transaction, it's also possible to contain many regular transactions
-within a long-running transaction, called a version in ZODB
-terminology.  Inside a version, any number of transactions can be
-created and committed or rolled back, but the changes within a version
-are not made visible to other connections to the same ZODB.
-
-<P>
-Not all storages support versions, but you can test for versioning
-ability by calling <tt class="method">supportsVersions()</tt> method of the
-<tt class="class">DB</tt> instance, which returns true if the underlying storage
-supports versioning.
-
-<P>
-A version can be selected when creating the <tt class="class">Connection</tt>
-instance using the <tt class="method">DB.open(<big>[</big><var>version</var><big>]</big>)</tt> method.
-The <var>version</var> argument must be a string that will be used as the
-name of the version.
+<H1><A NAME="SECTION000600000000000000000">
+5 Related Modules</A>
+</H1>
 
 <P>
-<dl><dd><pre class="verbatim">
-vers_conn = db.open(version='Working version')
-</pre></dl>
+The ZODB package includes a number of related modules that provide
+useful data types such as BTrees.
 
 <P>
-Transactions can then be committed and aborted using this versioned
-connection.  Other connections that don't specify a version, or
-provide a different version name, will not see changes committed
-within the version named "<tt class="samp">Working&nbsp;version</tt>".  To commit or abort a
-version, which will either make the changes visible to all clients or
-roll them back, call the <tt class="method">DB.commitVersion()</tt> or
-<tt class="method">DB.abortVersion()</tt> methods.
-XXX what are the source and dest arguments for?
 
-<P>
-The ZODB makes no attempt to reconcile changes between different
-versions.  Instead, the first version which modifies an object will
-gain a lock on that object.  Attempting to modify the object from a
-different version or from an unversioned connection will cause a
-<tt class="exception">ZODB.POSException.VersionLockError</tt> to be raised:
-
-<P>
-<dl><dd><pre class="verbatim">
-from ZODB.POSException import VersionLockError
-
-try:
-    get_transaction().commit()
-except VersionLockError, (obj_id, version):
-    print ('Cannot commit; object %s '
-           'locked by version %s' % (obj_id, version))
-</pre></dl>
-
-<P>
-The exception provides the ID of the locked object, and the name of
-the version having a lock on it.
+<p><hr>
+<!--Table of Child-Links-->
+<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
 
-<P>
+<UL>
+<LI><A href="node35.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
+<LI><A href="node36.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
+<LI><A href="node37.html">5.3 BTrees Package</a>
+</ul>
+<!--End of Table of Child-Links-->
 
 <DIV CLASS="navigation">
 <p><hr>
@@ -117,7 +76,7 @@ the version having a lock on it.
 <td><A HREF="node33.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node35.html"><img src="/python/writing/icons/next.gif"
@@ -134,11 +93,11 @@ the version having a lock on it.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node33.html">4.2 Undoing Changes</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node35.html">4.4 Multithreaded ZODB Programs</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node33.html">4.4 Multithreaded ZODB Programs</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node35.html">5.1 ZODB.PersistentMapping</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node35.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>4.4 Multithreaded ZODB Programs</title>
-<META NAME="description" CONTENT="4.4 Multithreaded ZODB Programs">
+<title>5.1 ZODB.PersistentMapping</title>
+<META NAME="description" CONTENT="5.1 ZODB.PersistentMapping">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
+<LINK REL="next" HREF="node36.html">
 <LINK REL="previous" HREF="node34.html">
-<LINK REL="up" HREF="node31.html">
+<LINK REL="up" HREF="node34.html">
 <LINK REL="next" HREF="node36.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -22,7 +24,7 @@
 <td><A HREF="node34.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node34.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node36.html"><img src="/python/writing/icons/next.gif"
@@ -39,26 +41,33 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node34.html">4.3 Versions</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node36.html">5.2 ZODB.PersistentList</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000540000000000000000">
-4.4 Multithreaded ZODB Programs</A>
+<H2><A NAME="SECTION000610000000000000000">
+5.1 <tt class="module">ZODB.PersistentMapping</tt></A>
 </H2>
 
 <P>
-ZODB databases can be accessed from multithreaded Python programs.
-The <tt class="class">Storage</tt> and <tt class="class">DB</tt> instances can be shared among
-several threads, as long as individual <tt class="class">Connection</tt> instances
-are created for each thread.  
+The <tt class="class">PersistentMapping</tt> class is a wrapper for mapping objects
+that will set the dirty bit when the mapping is modified by setting or
+deleting a key.  
+
+<P>
+<dl><dt><b><a name="l2h-1"><tt class="function">PersistentMapping</tt></a></b>(<var>container = {}</var>)
+<dd>
+Create a <tt class="class">PersistentMapping</tt> object that wraps the 
+mapping object <var>container</var>.  If you don't specify a
+value for <var>container</var>, a regular Python dictionary is used.
+</dl>
 
 <P>
-XXX I can't think of anything else to say about multithreaded ZODB
-programs.  Suggestions?  An example program?
+<tt class="class">PersistentMapping</tt> objects support all the same methods as 
+Python dictionaries do.
 
 <P>
 
@@ -69,7 +78,7 @@ programs.  Suggestions?  An example program?
 <td><A HREF="node34.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node31.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node34.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node36.html"><img src="/python/writing/icons/next.gif"
@@ -86,11 +95,11 @@ programs.  Suggestions?  An example program?
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node34.html">4.3 Versions</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node31.html">4 Transactions and Versioning</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node36.html">5.2 ZODB.PersistentList</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node36.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>5 Related Modules</title>
-<META NAME="description" CONTENT="5 Related Modules">
+<title>5.2 ZODB.PersistentList</title>
+<META NAME="description" CONTENT="5.2 ZODB.PersistentList">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node40.html">
-<LINK REL="previous" HREF="node31.html">
-<LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node37.html">
+<LINK REL="previous" HREF="node35.html">
+<LINK REL="up" HREF="node34.html">
+<LINK REL="next" HREF="node37.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node35.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node34.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node37.html"><img src="/python/writing/icons/next.gif"
@@ -40,33 +41,34 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node35.html">4.4 Multithreaded ZODB Programs</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node37.html">5.1 ZODB.PersistentMapping</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node35.html">5.1 ZODB.PersistentMapping</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node37.html">5.3 BTrees Package</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H1><A NAME="SECTION000600000000000000000">
-5 Related Modules</A>
-</H1>
+<H2><A NAME="SECTION000620000000000000000">
+5.2 <tt class="module">ZODB.PersistentList</tt></A>
+</H2>
 
 <P>
-The ZODB package includes a number of related modules that provide
-useful data types such as BTrees or full-text indexes.
+The <tt class="class">PersistentList</tt> class is a wrapper for mutable sequence objects, 
+much as <tt class="class">PersistentMapping</tt> is a wrapper for mappings.  
 
 <P>
+<dl><dt><b><a name="l2h-2"><tt class="function">PersistentList</tt></a></b>(<var>initlist = []</var>)
+<dd>
+Create a <tt class="class">PersistentList</tt> object that wraps the 
+mutable sequence object <var>initlist</var>.  If you don't specify a
+value for <var>initlist</var>, a regular Python list is used.
+</dl>
 
-<p><hr>
-<!--Table of Child-Links-->
-<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
+<P>
+<tt class="class">PersistentList</tt> objects support all the same methods as 
+Python lists do.
 
-<UL>
-<LI><A href="node37.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
-<LI><A href="node38.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
-<LI><A href="node39.html">5.3 B-tree Modules</a>
-</ul>
-<!--End of Table of Child-Links-->
+<P>
 
 <DIV CLASS="navigation">
 <p><hr>
@@ -75,7 +77,7 @@ useful data types such as BTrees or full-text indexes.
 <td><A HREF="node35.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node34.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node37.html"><img src="/python/writing/icons/next.gif"
@@ -92,11 +94,11 @@ useful data types such as BTrees or full-text indexes.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node35.html">4.4 Multithreaded ZODB Programs</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node37.html">5.1 ZODB.PersistentMapping</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node35.html">5.1 ZODB.PersistentMapping</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node37.html">5.3 BTrees Package</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node37.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>5.1 ZODB.PersistentMapping</title>
-<META NAME="description" CONTENT="5.1 ZODB.PersistentMapping">
+<title>5.3 BTrees Package</title>
+<META NAME="description" CONTENT="5.3 BTrees Package">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node38.html">
 <LINK REL="previous" HREF="node36.html">
-<LINK REL="up" HREF="node36.html">
+<LINK REL="up" HREF="node34.html">
 <LINK REL="next" HREF="node38.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +23,7 @@
 <td><A HREF="node36.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node36.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node34.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node38.html"><img src="/python/writing/icons/next.gif"
@@ -40,33 +40,114 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node38.html">5.2 ZODB.PersistentList</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node36.html">5.2 ZODB.PersistentList</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node38.html">A. Resources</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000610000000000000000">
-5.1 <tt class="module">ZODB.PersistentMapping</tt></A>
+<H2><A NAME="SECTION000630000000000000000">
+5.3 BTrees Package</A>
 </H2>
 
 <P>
-The <tt class="class">PersistentMapping</tt> class is a wrapper for mapping objects
-that will set the dirty bit when the mapping is modified by setting or
-deleting a key.  
+When programming with the ZODB, Python dictionaries aren't always what
+you need.  The most important case is where you want to store a very
+large mapping.  When a Python dictionary is accessed in a ZODB, the
+whole dictionary has to be unpickled and brought into memory.  If
+you're storing something very large, such as a 100,000-entry user
+database, unpickling such a large object will be slow.  BTrees are a
+balanced tree data structure that behave like a mapping but distribute
+keys throughout a number of tree nodes.  The nodes are stored in
+sorted order.  Nodes are then only unpickled and brought into memory
+as they're accessed, so the entire tree doesn't have to occupy memory
+(unless you really are touching every single key).
+
+<P>
+The BTrees package provides a large collection of related data
+structures.  There are variants of the data structures specialized to
+handle integer values, which are faster and use less memory.  There
+are four modules that handle the different variants.  The first two
+letters of the module name specify the types of the keys and values in
+mappings - O for any object and I for integer.  The
+<tt class="module">BTrees.IOBTree</tt> module provides a mapping that accepts integer
+keys and arbitrary objects as values.
+
+<P>
+The four data structures provide by each module are a btree, a bucket,
+a tree set, and a set.  The btree and bucket types are mappings and
+support all the usual mapping methods, e.g. <tt class="function">update()</tt> and
+<tt class="function">keys()</tt>.  The tree set and set types are similar to mappings
+but they have no values; they support the methods that make sense for
+a mapping with no keys, e.g. <tt class="function">keys()</tt> but not
+<tt class="function">items()</tt>.  The bucket and set types are the individual
+building blocks for btrees and tree sets, respectively.  A bucket or
+set can be used when you are sure that it will have few elements.  If
+the data structure will grow large, you should use a btree or tree
+set.
+
+<P>
+The four modules are named <tt class="module">OOBTree</tt>, <tt class="module">IOBTree</tt>,
+<tt class="module">OIBTree</tt>, and <tt class="module">IIBTree</tt>.  The two letter prefixes are
+repeated in the data types names.  The <tt class="module">BTrees.OOBTree</tt> module
+defines the following types: <tt class="class">OOBTree</tt>, <tt class="class">OOBucket</tt>,
+<tt class="class">OOSet</tt>, and <tt class="class">OOTreeSet</tt>.
 
 <P>
-<dl><dt><b><a name="l2h-1"><tt class="function">PersistentMapping</tt></a></b>(<var>container = {}</var>)
-<dd>
-Create a <tt class="class">PersistentMapping</tt> object that wraps the 
-mapping object <var>container</var>.  If you don't specify a
-value for <var>container</var>, a regular Python dictionary is used.
-</dl>
+The <tt class="function">keys()</tt>, <tt class="function">values()</tt>, and <tt class="function">items()</tt>
+methods do not materialize a list with all of the data.  Instead, they
+return lazy sequences that fetch data from the BTree as needed.  They
+also support optional arguments to specify the minium and maximum
+values to return.
 
 <P>
-<tt class="class">PersistentMapping</tt> objects support all the same methods as 
-Python dictionaries do.
+A BTree object supports all the methods you would expect of a mapping
+with a few extensions that exploit the fact that the keys are sorted.
+The example below demonstrates how some of the methods work.  The
+extra methods re <tt class="function">minKey()</tt> and <tt class="function">maxKey()</tt>, which
+find the minimum and maximum key value subject to an optional bound
+argument, and <tt class="function">byValue()</tt>, which returns value, key pairs
+in reversed sorted order subject to an optional minimum bound argument.
+
+<P>
+<div class="verbatim"><pre>
+&gt;&gt;&gt; from BTrees.OOBTree import OOBTree
+&gt;&gt;&gt; t = OOBTree()
+&gt;&gt;&gt; t.update({ 1: "red", 2: "green", 3: "blue", 4: "spades" })
+&gt;&gt;&gt; len(t)
+4
+&gt;&gt;&gt; t[2]
+'green'
+&gt;&gt;&gt; t.keys()
+&lt;OOBTreeItems object at 0x40269098&gt;
+&gt;&gt;&gt; [k for k in t.keys()] # use a listcomp to get a printable sequence
+[1, 2, 3, 4]
+&gt;&gt;&gt; [k for k in t.values()]
+['red', 'green', 'blue', 'spades']
+&gt;&gt;&gt; [k for k in t.values(1, 2)]
+['red', 'green']
+&gt;&gt;&gt; [k for k in t.values(2)]
+['green', 'blue', 'spades']
+&gt;&gt;&gt; t.byValue("glue") # all values &gt; "glue"
+[('spades', 4), ('red', 1), ('green', 2)]
+&gt;&gt;&gt; t.minKey(1.5)
+2
+</pre></div>
+
+<P>
+Each of the modules also defines some functions that operate on
+BTrees - <tt class="function">difference()</tt>, <tt class="function">union()</tt>, and
+<tt class="function">difference()</tt>.  The <tt class="function">difference()</tt> function returns
+a bucket, while the other two methods return a set.
+If the keys are integers, then the module also defines
+<tt class="function">multiunion()</tt>.  If the values are integers, then the module
+also defines <tt class="function">weightedIntersection()</tt> and
+<tt class="function">weighterUnion()</tt>.  The function doc strings describe each
+function briefly.
+
+<P>
+
 
 <P>
 
@@ -77,7 +158,7 @@ Python dictionaries do.
 <td><A HREF="node36.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node36.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node34.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node38.html"><img src="/python/writing/icons/next.gif"
@@ -94,11 +175,11 @@ Python dictionaries do.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node38.html">5.2 ZODB.PersistentList</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node36.html">5.2 ZODB.PersistentList</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node34.html">5 Related Modules</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node38.html">A. Resources</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node38.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>5.2 ZODB.PersistentList</title>
-<META NAME="description" CONTENT="5.2 ZODB.PersistentList">
+<title>A. Resources</title>
+<META NAME="description" CONTENT="A. Resources">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node39.html">
-<LINK REL="previous" HREF="node37.html">
-<LINK REL="up" HREF="node36.html">
+<LINK REL="previous" HREF="node34.html">
+<LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node39.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node37.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node36.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node39.html"><img src="/python/writing/icons/next.gif"
@@ -40,32 +41,45 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node37.html">5.1 ZODB.PersistentMapping</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node39.html">5.3 B-tree Modules</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node37.html">5.3 BTrees Package</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000620000000000000000">
-5.2 <tt class="module">ZODB.PersistentList</tt></A>
-</H2>
+<H1><A NAME="SECTION000700000000000000000">
+A. Resources</A>
+</H1>
 
 <P>
-The <tt class="class">PersistentList</tt> class is a wrapper for mutable sequence objects, 
-much as <tt class="class">PersistentMapping</tt> is a wrapper for mappings.  
+ZODB HOWTO, by Michel Pelletier:
 
+<BR>
+Goes into slightly more detail about the rules for writing applications using the ZODB.
+
+<BR><a class="url" href="http://www.zope.org/Members/michel/HowTos/ZODB-How-To">http://www.zope.org/Members/michel/HowTos/ZODB-How-To</a>
+<P>
+Introduction to the Zope Object Database, by Jim Fulton:
+
+<BR>
+Goes into much greater detail, explaining advanced uses of the ZODB and 
+how it's actually implemented.  A definitive reference, and highly recommended.
+
+<BR><a class="url" href="http://www.python.org/workshops/2000-01/proceedings/papers/fulton/zodb3.html">http://www.python.org/workshops/2000-01/proceedings/papers/fulton/zodb3.html</a>
 <P>
-<dl><dt><b><a name="l2h-2"><tt class="function">PersistentList</tt></a></b>(<var>initlist = []</var>)
-<dd>
-Create a <tt class="class">PersistentList</tt> object that wraps the 
-mutable sequence object <var>initlist</var>.  If you don't specify a
-value for <var>initlist</var>, a regular Python list is used.
-</dl>
+Persistent Programing with ZODB, by Jeremy Hylton and Barry Warsaw:
+
+<BR>
+Slides for a tutorial presented at the 10th Python conference.  Covers
+much of the same ground as this guide, with more details in some areas
+and less in others.
 
+<BR><a class="url" href="http://www.zope.org/Members/bwarsaw/ipc10-slides">http://www.zope.org/Members/bwarsaw/ipc10-slides</a>
+<P>
+Download link for ZEO: 
+<BR><a class="url" href="http://www.zope.org/Products/ZEO/">http://www.zope.org/Products/ZEO/</a>
 <P>
-<tt class="class">PersistentList</tt> objects support all the same methods as 
-Python lists do.
 
 <P>
 
@@ -76,7 +90,7 @@ Python lists do.
 <td><A HREF="node37.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node36.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node39.html"><img src="/python/writing/icons/next.gif"
@@ -93,11 +107,11 @@ Python lists do.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node37.html">5.1 ZODB.PersistentMapping</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node39.html">5.3 B-tree Modules</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node37.html">5.3 BTrees Package</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node39.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>5.3 B-tree Modules</title>
-<META NAME="description" CONTENT="5.3 B-tree Modules">
+<title>B. GNU Free Documentation License</title>
+<META NAME="description" CONTENT="B. GNU Free Documentation License">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
+<LINK REL="next" href="about.html">
 <LINK REL="previous" HREF="node38.html">
-<LINK REL="up" HREF="node36.html">
+<LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node40.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -22,7 +24,7 @@
 <td><A HREF="node38.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node36.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node40.html"><img src="/python/writing/icons/next.gif"
@@ -39,75 +41,52 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node38.html">5.2 ZODB.PersistentList</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node40.html">A. Resources</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node38.html">A. Resources</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node40.html">Preamble</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000630000000000000000">
-5.3 B-tree Modules</A>
-</H2>
+<H1><A NAME="SECTION000800000000000000000">
+B. GNU Free Documentation License</A>
+</H1>
 
 <P>
-When programming with the ZODB, Python dictionaries aren't always what
-you need.  The most important case is where you want to store a very
-large mapping.  When a Python dictionary is accessed in a ZODB, the
-whole dictionary has to be unpickled and brought into memory.  If
-you're storing something very large, such as a 100,000-entry user
-database, unpickling such a large object will be slow.  B-trees are a
-balanced tree data structure that behave like a mapping but distribute
-keys throughout a number of tree nodes.  Nodes are then only unpickled
-and brought into memory as they're accessed, so the entire tree
-doesn't have to occupy memory (unless you really are touching every
-single key).
-
-<P>
-There are four different BTree modules provided.  One of them, the
-<tt class="module">BTree</tt> module, provides the most general data type; the keys
-and values in the B-tree can be any Python object.  Some specialized B-tree
-modules require that the keys, and perhaps even the values, to be of a
-certain type, and provide faster performance because of this limitation.
-
-<P>
-<DL COMPACT>
-<DT> <tt class="module">IOBTree</tt> </DT>
-<DD>requires the keys to be integers.
-The module name reminds you of this; the <tt class="module">IOBTree</tt> module
-maps Integers to Objects.
-
-<P>
-</DD>
-<DT> <tt class="module">OIBTree</tt> </DT>
-<DD>requires the values to be integers,
-mapping Objects to Integers.
-
+Version 1.1, March 2000
+<BR>
 <P>
-</DD>
-<DT> <tt class="module">IIBTree</tt> </DT>
-<DD>is strictest, requiring that both keys and values must be integers.
-
-<P>
-</DD>
-</DL>
-
-<P>
-To use a B-tree, simply import the desired module and call the
-constructor, always named <tt class="function">BTree()</tt>, to get a B-tree
-instance, and then use it like any other mapping:
-
-<P>
-<dl><dd><pre class="verbatim">
-import IIBTree
-iimap = IIBTree.BTree()
-iimap[1972] = 27
-</pre></dl>
+Copyright <SPAN CLASS="MATH"><IMG
+ WIDTH="20" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
+ SRC="img1.gif"
+ ALT="$\copyright$"></SPAN> 2000  Free Software Foundation, Inc.
+<BR>
+59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+<BR>
+Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
 
 <P>
 
+<p><hr>
+<!--Table of Child-Links-->
+<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
 
-<P>
+<UL>
+<LI><A href="node40.html">Preamble</a>
+<LI><A href="node41.html">B..1 Applicability and Definitions</a>
+<LI><A href="node42.html">B..2 Verbatim Copying</a>
+<LI><A href="node43.html">B..3 Copying in Quantity</a>
+<LI><A href="node44.html">B..4 Modifications</a>
+<LI><A href="node45.html">B..5 Combining Documents</a>
+<LI><A href="node46.html">B..6 Collections of Documents</a>
+<LI><A href="node47.html">B..7 Aggregation With Independent Works</a>
+<LI><A href="node48.html">B..8 Translation</a>
+<LI><A href="node49.html">B..9 Termination</a>
+<LI><A href="node50.html">B..10 Future Revisions of This Licence</a>
+<LI><A href="node51.html">ADDENDUM: How to use this License for your documents</a>
+</ul>
+<!--End of Table of Child-Links-->
 
 <DIV CLASS="navigation">
 <p><hr>
@@ -116,7 +95,7 @@ iimap[1972] = 27
 <td><A HREF="node38.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node36.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node40.html"><img src="/python/writing/icons/next.gif"
@@ -133,11 +112,11 @@ iimap[1972] = 27
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node38.html">5.2 ZODB.PersistentList</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node36.html">5 Related Modules</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node40.html">A. Resources</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node38.html">A. Resources</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node40.html">Preamble</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node4.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node3.html">
 <LINK REL="up" HREF="node2.html">
 <LINK REL="next" HREF="node5.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -87,7 +88,7 @@ depositing, and 2) how much should be deposited.  You might deposit
 Mapping these structures to a relational database is straightforward:
 
 <P>
-<dl><dd><pre class="verbatim">
+<div class="verbatim"><pre>
 CREATE TABLE runs (
   int      run_id,
   varchar  owner,
@@ -113,7 +114,7 @@ CREATE TABLE parameters (
   FOREIGN KEY(run_id, step_num) 
      REFERENCES operations(run_id, step_num),
 );
-</pre></dl>
+</pre></div>
 
 <P>
 In Python, you would write three classes named <tt class="class">Run</tt>,
@@ -208,7 +209,7 @@ runs, therefore, is still inefficient, but not grossly inefficient.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node2.html">1 Introduction</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node5.html">1.3 What is ZEO?</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node40.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>A. Resources</title>
-<META NAME="description" CONTENT="A. Resources">
+<title>Preamble</title>
+<META NAME="description" CONTENT="Preamble">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node41.html">
-<LINK REL="previous" HREF="node36.html">
-<LINK REL="up" HREF="zodb.html">
+<LINK REL="previous" HREF="node39.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node41.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node39.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node41.html"><img src="/python/writing/icons/next.gif"
@@ -40,36 +41,40 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node39.html">5.3 B-tree Modules</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node41.html">B..1 Applicability and Definitions</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H1><A NAME="SECTION000700000000000000000">
-A. Resources</A>
-</H1>
+<H2><A NAME="SECTION000810000000000000000">
+Preamble</A>
+</H2>
 
 <P>
-ZODB HOWTO, by Michel Pelletier:
+The purpose of this License is to make a manual, textbook, or other
+written document ``free'' in the sense of freedom: to assure everyone
+the effective freedom to copy and redistribute it, with or without
+modifying it, either commercially or noncommercially.  Secondarily,
+this License preserves for the author and publisher a way to get
+credit for their work, while not being considered responsible for
+modifications made by others.
 
-<BR>
-Goes into slightly more detail about the rules for writing applications using the ZODB.
-
-<BR><a class="url" href="http://www.zope.org/Members/michel/HowTos/ZODB-How-To">http://www.zope.org/Members/michel/HowTos/ZODB-How-To</a>
 <P>
-Introduction to the Zope Object Database, by Jim Fulton:
-
-<BR>
-Goes into much greater detail, explaining advanced uses of the ZODB and 
-how it's actually implemented.  A definitive reference, and highly recommended.
+This License is a kind of ``copyleft'', which means that derivative
+works of the document must themselves be free in the same sense.  It
+complements the GNU General Public License, which is a copyleft
+license designed for free software.
 
-<BR><a class="url" href="http://www.python.org/workshops/2000-01/proceedings/papers/fulton/zodb3.html">http://www.python.org/workshops/2000-01/proceedings/papers/fulton/zodb3.html</a>
-<P>
-Download link for ZEO: 
-<BR><a class="url" href="http://www.zope.org/Products/ZEO/">http://www.zope.org/Products/ZEO/</a>
 <P>
+We have designed this License in order to use it for manuals for free
+software, because free software needs free documentation: a free
+program should come with manuals providing the same freedoms that the
+software does.  But this License is not limited to software manuals;
+it can be used for any textual work, regardless of subject matter or
+whether it is published as a printed book.  We recommend this License
+principally for works whose purpose is instruction or reference.
 
 <P>
 
@@ -80,7 +85,7 @@ Download link for ZEO:
 <td><A HREF="node39.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node41.html"><img src="/python/writing/icons/next.gif"
@@ -97,11 +102,11 @@ Download link for ZEO:
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node39.html">5.3 B-tree Modules</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node41.html">B..1 Applicability and Definitions</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node41.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B. GNU Free Documentation License</title>
-<META NAME="description" CONTENT="B. GNU Free Documentation License">
+<title>B..1 Applicability and Definitions</title>
+<META NAME="description" CONTENT="B..1 Applicability and Definitions">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" href="about.html">
+<LINK REL="next" HREF="node42.html">
 <LINK REL="previous" HREF="node40.html">
-<LINK REL="up" HREF="zodb.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node42.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node40.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node42.html"><img src="/python/writing/icons/next.gif"
@@ -40,52 +41,84 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node40.html">A. Resources</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node42.html">Preamble</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node40.html">Preamble</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node42.html">B..2 Verbatim Copying</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H1><A NAME="SECTION000800000000000000000">
-B. GNU Free Documentation License</A>
-</H1>
+<H2><A NAME="SECTION000820000000000000000">
+B..1 Applicability and Definitions</A>
+</H2>
 
 <P>
-Version 1.1, March 2000
-<BR>
+This License applies to any manual or other work that contains a
+notice placed by the copyright holder saying it can be distributed
+under the terms of this License.  The ``Document'', below, refers to any
+such manual or work.  Any member of the public is a licensee, and is
+addressed as ``you''.
+
 <P>
-Copyright <SPAN CLASS="MATH"><IMG
- WIDTH="20" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
- SRC="img1.gif"
- ALT="$\copyright$"></SPAN> 2000  Free Software Foundation, Inc.
-<BR>
-59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
-<BR>
-Everyone is permitted to copy and distribute verbatim copies
- of this license document, but changing it is not allowed.
+A ``Modified Version'' of the Document means any work containing the
+Document or a portion of it, either copied verbatim, or with
+modifications and/or translated into another language.
 
 <P>
+A ``Secondary Section'' is a named appendix or a front-matter section of
+the Document that deals exclusively with the relationship of the
+publishers or authors of the Document to the Document's overall subject
+(or to related matters) and contains nothing that could fall directly
+within that overall subject.  (For example, if the Document is in part a
+textbook of mathematics, a Secondary Section may not explain any
+mathematics.)  The relationship could be a matter of historical
+connection with the subject or with related matters, or of legal,
+commercial, philosophical, ethical or political position regarding
+them.
 
-<p><hr>
-<!--Table of Child-Links-->
-<A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
+<P>
+The ``Invariant Sections'' are certain Secondary Sections whose titles
+are designated, as being those of Invariant Sections, in the notice
+that says that the Document is released under this License.
 
-<UL>
-<LI><A href="node42.html">Preamble</a>
-<LI><A href="node43.html">B..1 Applicability and Definitions</a>
-<LI><A href="node44.html">B..2 Verbatim Copying</a>
-<LI><A href="node45.html">B..3 Copying in Quantity</a>
-<LI><A href="node46.html">B..4 Modifications</a>
-<LI><A href="node47.html">B..5 Combining Documents</a>
-<LI><A href="node48.html">B..6 Collections of Documents</a>
-<LI><A href="node49.html">B..7 Aggregation With Independent Works</a>
-<LI><A href="node50.html">B..8 Translation</a>
-<LI><A href="node51.html">B..9 Termination</a>
-<LI><A href="node52.html">B..10 Future Revisions of This Licence</a>
-<LI><A href="node53.html">ADDENDUM: How to use this License for your documents</a>
-</ul>
-<!--End of Table of Child-Links-->
+<P>
+The ``Cover Texts'' are certain short passages of text that are listed,
+as Front-Cover Texts or Back-Cover Texts, in the notice that says that
+the Document is released under this License.
+
+<P>
+A ``Transparent'' copy of the Document means a machine-readable copy,
+represented in a format whose specification is available to the
+general public, whose contents can be viewed and edited directly and
+straightforwardly with generic text editors or (for images composed of
+pixels) generic paint programs or (for drawings) some widely available
+drawing editor, and that is suitable for input to text formatters or
+for automatic translation to a variety of formats suitable for input
+to text formatters.  A copy made in an otherwise Transparent file
+format whose markup has been designed to thwart or discourage
+subsequent modification by readers is not Transparent.  A copy that is
+not ``Transparent'' is called ``Opaque''.
+
+<P>
+Examples of suitable formats for Transparent copies include plain
+ASCII without markup, Texinfo input format, <SPAN CLASS="logo,LaTeX">L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X</SPAN>&nbsp;input format, SGML
+or XML using a publicly available DTD, and standard-conforming simple
+HTML designed for human modification.  Opaque formats include
+PostScript, PDF, proprietary formats that can be read and edited only
+by proprietary word processors, SGML or XML for which the DTD and/or
+processing tools are not generally available, and the
+machine-generated HTML produced by some word processors for output
+purposes only.
+
+<P>
+The ``Title Page'' means, for a printed book, the title page itself,
+plus such following pages as are needed to hold, legibly, the material
+this License requires to appear in the title page.  For works in
+formats which do not have any title page as such, ``Title Page'' means
+the text near the most prominent appearance of the work's title,
+preceding the beginning of the body of the text.
+
+<P>
 
 <DIV CLASS="navigation">
 <p><hr>
@@ -94,7 +127,7 @@ Everyone is permitted to copy and distribute verbatim copies
 <td><A HREF="node40.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node42.html"><img src="/python/writing/icons/next.gif"
@@ -111,11 +144,11 @@ Everyone is permitted to copy and distribute verbatim copies
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node40.html">A. Resources</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node42.html">Preamble</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node40.html">Preamble</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node42.html">B..2 Verbatim Copying</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node42.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>Preamble</title>
-<META NAME="description" CONTENT="Preamble">
+<title>B..2 Verbatim Copying</title>
+<META NAME="description" CONTENT="B..2 Verbatim Copying">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node43.html">
 <LINK REL="previous" HREF="node41.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node43.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node41.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node43.html"><img src="/python/writing/icons/next.gif"
@@ -40,40 +41,31 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node43.html">B..1 Applicability and Definitions</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node41.html">B..1 Applicability and Definitions</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node43.html">B..3 Copying in Quantity</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000810000000000000000">
-Preamble</A>
+<H2><A NAME="SECTION000830000000000000000">
+B..2 Verbatim Copying</A>
 </H2>
 
 <P>
-The purpose of this License is to make a manual, textbook, or other
-written document ``free'' in the sense of freedom: to assure everyone
-the effective freedom to copy and redistribute it, with or without
-modifying it, either commercially or noncommercially.  Secondarily,
-this License preserves for the author and publisher a way to get
-credit for their work, while not being considered responsible for
-modifications made by others.
+You may copy and distribute the Document in any medium, either
+commercially or noncommercially, provided that this License, the
+copyright notices, and the license notice saying this License applies
+to the Document are reproduced in all copies, and that you add no other
+conditions whatsoever to those of this License.  You may not use
+technical measures to obstruct or control the reading or further
+copying of the copies you make or distribute.  However, you may accept
+compensation in exchange for copies.  If you distribute a large enough
+number of copies you must also follow the conditions in section 3.
 
 <P>
-This License is a kind of ``copyleft'', which means that derivative
-works of the document must themselves be free in the same sense.  It
-complements the GNU General Public License, which is a copyleft
-license designed for free software.
-
-<P>
-We have designed this License in order to use it for manuals for free
-software, because free software needs free documentation: a free
-program should come with manuals providing the same freedoms that the
-software does.  But this License is not limited to software manuals;
-it can be used for any textual work, regardless of subject matter or
-whether it is published as a printed book.  We recommend this License
-principally for works whose purpose is instruction or reference.
+You may also lend copies, under the same conditions stated above, and
+you may publicly display copies.
 
 <P>
 
@@ -84,7 +76,7 @@ principally for works whose purpose is instruction or reference.
 <td><A HREF="node41.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node43.html"><img src="/python/writing/icons/next.gif"
@@ -101,11 +93,11 @@ principally for works whose purpose is instruction or reference.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node43.html">B..1 Applicability and Definitions</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node41.html">B..1 Applicability and Definitions</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node43.html">B..3 Copying in Quantity</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node43.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..1 Applicability and Definitions</title>
-<META NAME="description" CONTENT="B..1 Applicability and Definitions">
+<title>B..3 Copying in Quantity</title>
+<META NAME="description" CONTENT="B..3 Copying in Quantity">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node44.html">
 <LINK REL="previous" HREF="node42.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node44.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node42.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node44.html"><img src="/python/writing/icons/next.gif"
@@ -40,82 +41,55 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node42.html">Preamble</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node44.html">B..2 Verbatim Copying</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node42.html">B..2 Verbatim Copying</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node44.html">B..4 Modifications</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000820000000000000000">
-B..1 Applicability and Definitions</A>
+<H2><A NAME="SECTION000840000000000000000">
+B..3 Copying in Quantity</A>
 </H2>
 
 <P>
-This License applies to any manual or other work that contains a
-notice placed by the copyright holder saying it can be distributed
-under the terms of this License.  The ``Document'', below, refers to any
-such manual or work.  Any member of the public is a licensee, and is
-addressed as ``you''.
+If you publish printed copies of the Document numbering more than 100,
+and the Document's license notice requires Cover Texts, you must enclose
+the copies in covers that carry, clearly and legibly, all these Cover
+Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
+the back cover.  Both covers must also clearly and legibly identify
+you as the publisher of these copies.  The front cover must present
+the full title with all words of the title equally prominent and
+visible.  You may add other material on the covers in addition.
+Copying with changes limited to the covers, as long as they preserve
+the title of the Document and satisfy these conditions, can be treated
+as verbatim copying in other respects.
 
 <P>
-A ``Modified Version'' of the Document means any work containing the
-Document or a portion of it, either copied verbatim, or with
-modifications and/or translated into another language.
+If the required texts for either cover are too voluminous to fit
+legibly, you should put the first ones listed (as many as fit
+reasonably) on the actual cover, and continue the rest onto adjacent
+pages.
 
 <P>
-A ``Secondary Section'' is a named appendix or a front-matter section of
-the Document that deals exclusively with the relationship of the
-publishers or authors of the Document to the Document's overall subject
-(or to related matters) and contains nothing that could fall directly
-within that overall subject.  (For example, if the Document is in part a
-textbook of mathematics, a Secondary Section may not explain any
-mathematics.)  The relationship could be a matter of historical
-connection with the subject or with related matters, or of legal,
-commercial, philosophical, ethical or political position regarding
-them.
+If you publish or distribute Opaque copies of the Document numbering
+more than 100, you must either include a machine-readable Transparent
+copy along with each Opaque copy, or state in or with each Opaque copy
+a publicly-accessible computer-network location containing a complete
+Transparent copy of the Document, free of added material, which the
+general network-using public has access to download anonymously at no
+charge using public-standard network protocols.  If you use the latter
+option, you must take reasonably prudent steps, when you begin
+distribution of Opaque copies in quantity, to ensure that this
+Transparent copy will remain thus accessible at the stated location
+until at least one year after the last time you distribute an Opaque
+copy (directly or through your agents or retailers) of that edition to
+the public.
 
 <P>
-The ``Invariant Sections'' are certain Secondary Sections whose titles
-are designated, as being those of Invariant Sections, in the notice
-that says that the Document is released under this License.
-
-<P>
-The ``Cover Texts'' are certain short passages of text that are listed,
-as Front-Cover Texts or Back-Cover Texts, in the notice that says that
-the Document is released under this License.
-
-<P>
-A ``Transparent'' copy of the Document means a machine-readable copy,
-represented in a format whose specification is available to the
-general public, whose contents can be viewed and edited directly and
-straightforwardly with generic text editors or (for images composed of
-pixels) generic paint programs or (for drawings) some widely available
-drawing editor, and that is suitable for input to text formatters or
-for automatic translation to a variety of formats suitable for input
-to text formatters.  A copy made in an otherwise Transparent file
-format whose markup has been designed to thwart or discourage
-subsequent modification by readers is not Transparent.  A copy that is
-not ``Transparent'' is called ``Opaque''.
-
-<P>
-Examples of suitable formats for Transparent copies include plain
-ASCII without markup, Texinfo input format, <SPAN CLASS="logo,LaTeX">L<SUP><SMALL>A</SMALL></SUP>T<SMALL>E</SMALL>X</SPAN>&nbsp;input format, SGML
-or XML using a publicly available DTD, and standard-conforming simple
-HTML designed for human modification.  Opaque formats include
-PostScript, PDF, proprietary formats that can be read and edited only
-by proprietary word processors, SGML or XML for which the DTD and/or
-processing tools are not generally available, and the
-machine-generated HTML produced by some word processors for output
-purposes only.
-
-<P>
-The ``Title Page'' means, for a printed book, the title page itself,
-plus such following pages as are needed to hold, legibly, the material
-this License requires to appear in the title page.  For works in
-formats which do not have any title page as such, ``Title Page'' means
-the text near the most prominent appearance of the work's title,
-preceding the beginning of the body of the text.
+It is requested, but not required, that you contact the authors of the
+Document well before redistributing any large number of copies, to give
+them a chance to provide you with an updated version of the Document.
 
 <P>
 
@@ -126,7 +100,7 @@ preceding the beginning of the body of the text.
 <td><A HREF="node42.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node44.html"><img src="/python/writing/icons/next.gif"
@@ -143,11 +117,11 @@ preceding the beginning of the body of the text.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node42.html">Preamble</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node44.html">B..2 Verbatim Copying</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node42.html">B..2 Verbatim Copying</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node44.html">B..4 Modifications</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node44.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..2 Verbatim Copying</title>
-<META NAME="description" CONTENT="B..2 Verbatim Copying">
+<title>B..4 Modifications</title>
+<META NAME="description" CONTENT="B..4 Modifications">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node45.html">
 <LINK REL="previous" HREF="node43.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node45.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node43.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node45.html"><img src="/python/writing/icons/next.gif"
@@ -40,31 +41,121 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node43.html">B..1 Applicability and Definitions</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node45.html">B..3 Copying in Quantity</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node43.html">B..3 Copying in Quantity</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node45.html">B..5 Combining Documents</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000830000000000000000">
-B..2 Verbatim Copying</A>
+<H2><A NAME="SECTION000850000000000000000">
+B..4 Modifications</A>
 </H2>
 
 <P>
-You may copy and distribute the Document in any medium, either
-commercially or noncommercially, provided that this License, the
-copyright notices, and the license notice saying this License applies
-to the Document are reproduced in all copies, and that you add no other
-conditions whatsoever to those of this License.  You may not use
-technical measures to obstruct or control the reading or further
-copying of the copies you make or distribute.  However, you may accept
-compensation in exchange for copies.  If you distribute a large enough
-number of copies you must also follow the conditions in section 3.
+You may copy and distribute a Modified Version of the Document under
+the conditions of sections 2 and 3 above, provided that you release
+the Modified Version under precisely this License, with the Modified
+Version filling the role of the Document, thus licensing distribution
+and modification of the Modified Version to whoever possesses a copy
+of it.  In addition, you must do these things in the Modified Version:
 
 <P>
-You may also lend copies, under the same conditions stated above, and
-you may publicly display copies.
+
+<UL>
+<LI>Use in the Title Page (and on the covers, if any) a title distinct
+   from that of the Document, and from those of previous versions
+   (which should, if there were any, be listed in the History section
+   of the Document).  You may use the same title as a previous version
+   if the original publisher of that version gives permission.
+</LI>
+<LI>List on the Title Page, as authors, one or more persons or entities
+   responsible for authorship of the modifications in the Modified
+   Version, together with at least five of the principal authors of the
+   Document (all of its principal authors, if it has less than five).
+</LI>
+<LI>State on the Title page the name of the publisher of the
+   Modified Version, as the publisher.
+</LI>
+<LI>Preserve all the copyright notices of the Document.
+</LI>
+<LI>Add an appropriate copyright notice for your modifications
+   adjacent to the other copyright notices.
+</LI>
+<LI>Include, immediately after the copyright notices, a license notice
+   giving the public permission to use the Modified Version under the
+   terms of this License, in the form shown in the Addendum below.
+</LI>
+<LI>Preserve in that license notice the full lists of Invariant Sections
+   and required Cover Texts given in the Document's license notice.
+</LI>
+<LI>Include an unaltered copy of this License.
+</LI>
+<LI>Preserve the section entitled ``History'', and its title, and add to
+   it an item stating at least the title, year, new authors, and
+   publisher of the Modified Version as given on the Title Page.  If
+   there is no section entitled ``History'' in the Document, create one
+   stating the title, year, authors, and publisher of the Document as
+   given on its Title Page, then add an item describing the Modified
+   Version as stated in the previous sentence.
+</LI>
+<LI>Preserve the network location, if any, given in the Document for
+   public access to a Transparent copy of the Document, and likewise
+   the network locations given in the Document for previous versions
+   it was based on.  These may be placed in the ``History'' section.
+   You may omit a network location for a work that was published at
+   least four years before the Document itself, or if the original
+   publisher of the version it refers to gives permission.
+</LI>
+<LI>In any section entitled ``Acknowledgements'' or ``Dedications'',
+   preserve the section's title, and preserve in the section all the
+   substance and tone of each of the contributor acknowledgements
+   and/or dedications given therein.
+</LI>
+<LI>Preserve all the Invariant Sections of the Document,
+   unaltered in their text and in their titles.  Section numbers
+   or the equivalent are not considered part of the section titles.
+</LI>
+<LI>Delete any section entitled ``Endorsements''.  Such a section
+   may not be included in the Modified Version.
+</LI>
+<LI>Do not retitle any existing section as ``Endorsements''
+   or to conflict in title with any Invariant Section.
+
+<P>
+</LI>
+</UL>
+
+<P>
+If the Modified Version includes new front-matter sections or
+appendices that qualify as Secondary Sections and contain no material
+copied from the Document, you may at your option designate some or all
+of these sections as invariant.  To do this, add their titles to the
+list of Invariant Sections in the Modified Version's license notice.
+These titles must be distinct from any other section titles.
+
+<P>
+You may add a section entitled ``Endorsements'', provided it contains
+nothing but endorsements of your Modified Version by various
+parties - for example, statements of peer review or that the text has
+been approved by an organization as the authoritative definition of a
+standard.
+
+<P>
+You may add a passage of up to five words as a Front-Cover Text, and a
+passage of up to 25 words as a Back-Cover Text, to the end of the list
+of Cover Texts in the Modified Version.  Only one passage of
+Front-Cover Text and one of Back-Cover Text may be added by (or
+through arrangements made by) any one entity.  If the Document already
+includes a cover text for the same cover, previously added by you or
+by arrangement made by the same entity you are acting on behalf of,
+you may not add another; but you may replace the old one, on explicit
+permission from the previous publisher that added the old one.
+
+<P>
+The author(s) and publisher(s) of the Document do not by this License
+give permission to use their names for publicity for or to assert or
+imply endorsement of any Modified Version.
 
 <P>
 
@@ -75,7 +166,7 @@ you may publicly display copies.
 <td><A HREF="node43.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node45.html"><img src="/python/writing/icons/next.gif"
@@ -92,11 +183,11 @@ you may publicly display copies.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node43.html">B..1 Applicability and Definitions</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node45.html">B..3 Copying in Quantity</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node43.html">B..3 Copying in Quantity</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node45.html">B..5 Combining Documents</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node45.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..3 Copying in Quantity</title>
-<META NAME="description" CONTENT="B..3 Copying in Quantity">
+<title>B..5 Combining Documents</title>
+<META NAME="description" CONTENT="B..5 Combining Documents">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node46.html">
 <LINK REL="previous" HREF="node44.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node46.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node44.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node46.html"><img src="/python/writing/icons/next.gif"
@@ -40,55 +41,41 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node44.html">B..2 Verbatim Copying</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node46.html">B..4 Modifications</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node44.html">B..4 Modifications</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node46.html">B..6 Collections of Documents</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000840000000000000000">
-B..3 Copying in Quantity</A>
+<H2><A NAME="SECTION000860000000000000000">
+B..5 Combining Documents</A>
 </H2>
 
 <P>
-If you publish printed copies of the Document numbering more than 100,
-and the Document's license notice requires Cover Texts, you must enclose
-the copies in covers that carry, clearly and legibly, all these Cover
-Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on
-the back cover.  Both covers must also clearly and legibly identify
-you as the publisher of these copies.  The front cover must present
-the full title with all words of the title equally prominent and
-visible.  You may add other material on the covers in addition.
-Copying with changes limited to the covers, as long as they preserve
-the title of the Document and satisfy these conditions, can be treated
-as verbatim copying in other respects.
+You may combine the Document with other documents released under this
+License, under the terms defined in section 4 above for modified
+versions, provided that you include in the combination all of the
+Invariant Sections of all of the original documents, unmodified, and
+list them all as Invariant Sections of your combined work in its
+license notice.
 
 <P>
-If the required texts for either cover are too voluminous to fit
-legibly, you should put the first ones listed (as many as fit
-reasonably) on the actual cover, and continue the rest onto adjacent
-pages.
+The combined work need only contain one copy of this License, and
+multiple identical Invariant Sections may be replaced with a single
+copy.  If there are multiple Invariant Sections with the same name but
+different contents, make the title of each such section unique by
+adding at the end of it, in parentheses, the name of the original
+author or publisher of that section if known, or else a unique number.
+Make the same adjustment to the section titles in the list of
+Invariant Sections in the license notice of the combined work.
 
 <P>
-If you publish or distribute Opaque copies of the Document numbering
-more than 100, you must either include a machine-readable Transparent
-copy along with each Opaque copy, or state in or with each Opaque copy
-a publicly-accessible computer-network location containing a complete
-Transparent copy of the Document, free of added material, which the
-general network-using public has access to download anonymously at no
-charge using public-standard network protocols.  If you use the latter
-option, you must take reasonably prudent steps, when you begin
-distribution of Opaque copies in quantity, to ensure that this
-Transparent copy will remain thus accessible at the stated location
-until at least one year after the last time you distribute an Opaque
-copy (directly or through your agents or retailers) of that edition to
-the public.
-
-<P>
-It is requested, but not required, that you contact the authors of the
-Document well before redistributing any large number of copies, to give
-them a chance to provide you with an updated version of the Document.
+In the combination, you must combine any sections entitled ``History''
+in the various original documents, forming one section entitled
+``History''; likewise combine any sections entitled ``Acknowledgements'',
+and any sections entitled ``Dedications''.  You must delete all sections
+entitled ``Endorsements.''
 
 <P>
 
@@ -99,7 +86,7 @@ them a chance to provide you with an updated version of the Document.
 <td><A HREF="node44.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node46.html"><img src="/python/writing/icons/next.gif"
@@ -116,11 +103,11 @@ them a chance to provide you with an updated version of the Document.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node44.html">B..2 Verbatim Copying</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node46.html">B..4 Modifications</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node44.html">B..4 Modifications</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node46.html">B..6 Collections of Documents</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node46.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..4 Modifications</title>
-<META NAME="description" CONTENT="B..4 Modifications">
+<title>B..6 Collections of Documents</title>
+<META NAME="description" CONTENT="B..6 Collections of Documents">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node47.html">
 <LINK REL="previous" HREF="node45.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node47.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node45.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node47.html"><img src="/python/writing/icons/next.gif"
@@ -40,121 +41,29 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node45.html">B..3 Copying in Quantity</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node47.html">B..5 Combining Documents</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node45.html">B..5 Combining Documents</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node47.html">B..7 Aggregation With Independent</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000850000000000000000">
-B..4 Modifications</A>
+<H2><A NAME="SECTION000870000000000000000">
+B..6 Collections of Documents</A>
 </H2>
 
 <P>
-You may copy and distribute a Modified Version of the Document under
-the conditions of sections 2 and 3 above, provided that you release
-the Modified Version under precisely this License, with the Modified
-Version filling the role of the Document, thus licensing distribution
-and modification of the Modified Version to whoever possesses a copy
-of it.  In addition, you must do these things in the Modified Version:
+You may make a collection consisting of the Document and other documents
+released under this License, and replace the individual copies of this
+License in the various documents with a single copy that is included in
+the collection, provided that you follow the rules of this License for
+verbatim copying of each of the documents in all other respects.
 
 <P>
-
-<UL>
-<LI>Use in the Title Page (and on the covers, if any) a title distinct
-   from that of the Document, and from those of previous versions
-   (which should, if there were any, be listed in the History section
-   of the Document).  You may use the same title as a previous version
-   if the original publisher of that version gives permission.
-</LI>
-<LI>List on the Title Page, as authors, one or more persons or entities
-   responsible for authorship of the modifications in the Modified
-   Version, together with at least five of the principal authors of the
-   Document (all of its principal authors, if it has less than five).
-</LI>
-<LI>State on the Title page the name of the publisher of the
-   Modified Version, as the publisher.
-</LI>
-<LI>Preserve all the copyright notices of the Document.
-</LI>
-<LI>Add an appropriate copyright notice for your modifications
-   adjacent to the other copyright notices.
-</LI>
-<LI>Include, immediately after the copyright notices, a license notice
-   giving the public permission to use the Modified Version under the
-   terms of this License, in the form shown in the Addendum below.
-</LI>
-<LI>Preserve in that license notice the full lists of Invariant Sections
-   and required Cover Texts given in the Document's license notice.
-</LI>
-<LI>Include an unaltered copy of this License.
-</LI>
-<LI>Preserve the section entitled ``History'', and its title, and add to
-   it an item stating at least the title, year, new authors, and
-   publisher of the Modified Version as given on the Title Page.  If
-   there is no section entitled ``History'' in the Document, create one
-   stating the title, year, authors, and publisher of the Document as
-   given on its Title Page, then add an item describing the Modified
-   Version as stated in the previous sentence.
-</LI>
-<LI>Preserve the network location, if any, given in the Document for
-   public access to a Transparent copy of the Document, and likewise
-   the network locations given in the Document for previous versions
-   it was based on.  These may be placed in the ``History'' section.
-   You may omit a network location for a work that was published at
-   least four years before the Document itself, or if the original
-   publisher of the version it refers to gives permission.
-</LI>
-<LI>In any section entitled ``Acknowledgements'' or ``Dedications'',
-   preserve the section's title, and preserve in the section all the
-   substance and tone of each of the contributor acknowledgements
-   and/or dedications given therein.
-</LI>
-<LI>Preserve all the Invariant Sections of the Document,
-   unaltered in their text and in their titles.  Section numbers
-   or the equivalent are not considered part of the section titles.
-</LI>
-<LI>Delete any section entitled ``Endorsements''.  Such a section
-   may not be included in the Modified Version.
-</LI>
-<LI>Do not retitle any existing section as ``Endorsements''
-   or to conflict in title with any Invariant Section.
-
-<P>
-</LI>
-</UL>
-
-<P>
-If the Modified Version includes new front-matter sections or
-appendices that qualify as Secondary Sections and contain no material
-copied from the Document, you may at your option designate some or all
-of these sections as invariant.  To do this, add their titles to the
-list of Invariant Sections in the Modified Version's license notice.
-These titles must be distinct from any other section titles.
-
-<P>
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-nothing but endorsements of your Modified Version by various
-parties - for example, statements of peer review or that the text has
-been approved by an organization as the authoritative definition of a
-standard.
-
-<P>
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-Front-Cover Text and one of Back-Cover Text may be added by (or
-through arrangements made by) any one entity.  If the Document already
-includes a cover text for the same cover, previously added by you or
-by arrangement made by the same entity you are acting on behalf of,
-you may not add another; but you may replace the old one, on explicit
-permission from the previous publisher that added the old one.
-
-<P>
-The author(s) and publisher(s) of the Document do not by this License
-give permission to use their names for publicity for or to assert or
-imply endorsement of any Modified Version.
+You may extract a single document from such a collection, and distribute
+it individually under this License, provided you insert a copy of this
+License into the extracted document, and follow this License in all
+other respects regarding verbatim copying of that document.
 
 <P>
 
@@ -165,7 +74,7 @@ imply endorsement of any Modified Version.
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-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
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 <td><A HREF="node47.html"><img src="/python/writing/icons/next.gif"
@@ -182,11 +91,11 @@ imply endorsement of any Modified Version.
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-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node45.html">B..3 Copying in Quantity</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node47.html">B..5 Combining Documents</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node45.html">B..5 Combining Documents</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node47.html">B..7 Aggregation With Independent</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node47.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..5 Combining Documents</title>
-<META NAME="description" CONTENT="B..5 Combining Documents">
+<title>B..7 Aggregation With Independent Works</title>
+<META NAME="description" CONTENT="B..7 Aggregation With Independent Works">
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+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
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 <LINK REL="next" HREF="node48.html">
 <LINK REL="previous" HREF="node46.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node48.html">
+<meta name='aesop' content='information'>
 </head>
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@@ -23,7 +24,7 @@
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   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
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 <td><A HREF="node48.html"><img src="/python/writing/icons/next.gif"
@@ -40,41 +41,33 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node46.html">B..4 Modifications</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node48.html">B..6 Collections of Documents</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node46.html">B..6 Collections of Documents</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node48.html">B..8 Translation</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000860000000000000000">
-B..5 Combining Documents</A>
+<H2><A NAME="SECTION000880000000000000000">
+B..7 Aggregation With Independent Works</A>
 </H2>
 
 <P>
-You may combine the Document with other documents released under this
-License, under the terms defined in section 4 above for modified
-versions, provided that you include in the combination all of the
-Invariant Sections of all of the original documents, unmodified, and
-list them all as Invariant Sections of your combined work in its
-license notice.
+A compilation of the Document or its derivatives with other separate
+and independent documents or works, in or on a volume of a storage or
+distribution medium, does not as a whole count as a Modified Version
+of the Document, provided no compilation copyright is claimed for the
+compilation.  Such a compilation is called an ``aggregate'', and this
+License does not apply to the other self-contained works thus compiled
+with the Document, on account of their being thus compiled, if they
+are not themselves derivative works of the Document.
 
 <P>
-The combined work need only contain one copy of this License, and
-multiple identical Invariant Sections may be replaced with a single
-copy.  If there are multiple Invariant Sections with the same name but
-different contents, make the title of each such section unique by
-adding at the end of it, in parentheses, the name of the original
-author or publisher of that section if known, or else a unique number.
-Make the same adjustment to the section titles in the list of
-Invariant Sections in the license notice of the combined work.
-
-<P>
-In the combination, you must combine any sections entitled ``History''
-in the various original documents, forming one section entitled
-``History''; likewise combine any sections entitled ``Acknowledgements'',
-and any sections entitled ``Dedications''.  You must delete all sections
-entitled ``Endorsements.''
+If the Cover Text requirement of section 3 is applicable to these
+copies of the Document, then if the Document is less than one quarter
+of the entire aggregate, the Document's Cover Texts may be placed on
+covers that surround only the Document within the aggregate.
+Otherwise they must appear on covers around the whole aggregate.
 
 <P>
 
@@ -85,7 +78,7 @@ entitled ``Endorsements.''
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   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node48.html"><img src="/python/writing/icons/next.gif"
@@ -102,11 +95,11 @@ entitled ``Endorsements.''
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node46.html">B..4 Modifications</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node48.html">B..6 Collections of Documents</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node46.html">B..6 Collections of Documents</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node48.html">B..8 Translation</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node48.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..6 Collections of Documents</title>
-<META NAME="description" CONTENT="B..6 Collections of Documents">
+<title>B..8 Translation</title>
+<META NAME="description" CONTENT="B..8 Translation">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
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 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node49.html">
 <LINK REL="previous" HREF="node47.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node49.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node47.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
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 <td><A HREF="node49.html"><img src="/python/writing/icons/next.gif"
@@ -40,29 +41,28 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node47.html">B..5 Combining Documents</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node49.html">B..7 Aggregation With Independent</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node47.html">B..7 Aggregation With Independent</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node49.html">B..9 Termination</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000870000000000000000">
-B..6 Collections of Documents</A>
+<H2><A NAME="SECTION000890000000000000000">
+B..8 Translation</A>
 </H2>
 
 <P>
-You may make a collection consisting of the Document and other documents
-released under this License, and replace the individual copies of this
-License in the various documents with a single copy that is included in
-the collection, provided that you follow the rules of this License for
-verbatim copying of each of the documents in all other respects.
-
-<P>
-You may extract a single document from such a collection, and distribute
-it individually under this License, provided you insert a copy of this
-License into the extracted document, and follow this License in all
-other respects regarding verbatim copying of that document.
+Translation is considered a kind of modification, so you may
+distribute translations of the Document under the terms of section 4.
+Replacing Invariant Sections with translations requires special
+permission from their copyright holders, but you may include
+translations of some or all Invariant Sections in addition to the
+original versions of these Invariant Sections.  You may include a
+translation of this License provided that you also include the
+original English version of this License.  In case of a disagreement
+between the translation and the original English version of this
+License, the original English version will prevail.
 
 <P>
 
@@ -73,7 +73,7 @@ other respects regarding verbatim copying of that document.
 <td><A HREF="node47.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node49.html"><img src="/python/writing/icons/next.gif"
@@ -90,11 +90,11 @@ other respects regarding verbatim copying of that document.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node47.html">B..5 Combining Documents</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node49.html">B..7 Aggregation With Independent</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node47.html">B..7 Aggregation With Independent</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node49.html">B..9 Termination</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node49.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..7 Aggregation With Independent Works</title>
-<META NAME="description" CONTENT="B..7 Aggregation With Independent Works">
+<title>B..9 Termination</title>
+<META NAME="description" CONTENT="B..9 Termination">
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 <META NAME="distribution" CONTENT="global">
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-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
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 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node50.html">
 <LINK REL="previous" HREF="node48.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node50.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,7 +24,7 @@
 <td><A HREF="node48.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node50.html"><img src="/python/writing/icons/next.gif"
@@ -40,33 +41,25 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node48.html">B..6 Collections of Documents</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node50.html">B..8 Translation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node48.html">B..8 Translation</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node50.html">B..10 Future Revisions of</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000880000000000000000">
-B..7 Aggregation With Independent Works</A>
+<H2><A NAME="SECTION0008100000000000000000">
+B..9 Termination</A>
 </H2>
 
 <P>
-A compilation of the Document or its derivatives with other separate
-and independent documents or works, in or on a volume of a storage or
-distribution medium, does not as a whole count as a Modified Version
-of the Document, provided no compilation copyright is claimed for the
-compilation.  Such a compilation is called an ``aggregate'', and this
-License does not apply to the other self-contained works thus compiled
-with the Document, on account of their being thus compiled, if they
-are not themselves derivative works of the Document.
-
-<P>
-If the Cover Text requirement of section 3 is applicable to these
-copies of the Document, then if the Document is less than one quarter
-of the entire aggregate, the Document's Cover Texts may be placed on
-covers that surround only the Document within the aggregate.
-Otherwise they must appear on covers around the whole aggregate.
+You may not copy, modify, sublicense, or distribute the Document except
+as expressly provided for under this License.  Any other attempt to
+copy, modify, sublicense or distribute the Document is void, and will
+automatically terminate your rights under this License.  However,
+parties who have received copies, or rights, from you under this
+License will not have their licenses terminated so long as such
+parties remain in full compliance.
 
 <P>
 
@@ -77,7 +70,7 @@ Otherwise they must appear on covers around the whole aggregate.
 <td><A HREF="node48.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node50.html"><img src="/python/writing/icons/next.gif"
@@ -94,11 +87,11 @@ Otherwise they must appear on covers around the whole aggregate.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node48.html">B..6 Collections of Documents</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node50.html">B..8 Translation</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node48.html">B..8 Translation</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node50.html">B..10 Future Revisions of</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node5.html

@@ -6,8 +6,8 @@
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
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-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node4.html">
 <LINK REL="up" HREF="node2.html">
 <LINK REL="next" HREF="node6.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -95,7 +96,7 @@ we'll see later on in this document, it opens up many possibilities.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node2.html">1 Introduction</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node6.html">1.4 About this guide</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node50.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..8 Translation</title>
-<META NAME="description" CONTENT="B..8 Translation">
+<title>B..10 Future Revisions of This Licence</title>
+<META NAME="description" CONTENT="B..10 Future Revisions of This Licence">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" HREF="node51.html">
 <LINK REL="previous" HREF="node49.html">
-<LINK REL="up" HREF="node41.html">
+<LINK REL="up" HREF="node39.html">
 <LINK REL="next" HREF="node51.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
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@@ -23,7 +24,7 @@
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-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
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@@ -40,28 +41,33 @@
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-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node51.html">B..9 Termination</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node49.html">B..9 Termination</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node51.html">ADDENDUM: How to use</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION000890000000000000000">
-B..8 Translation</A>
+<H2><A NAME="SECTION0008110000000000000000">
+B..10 Future Revisions of This Licence</A>
 </H2>
 
 <P>
-Translation is considered a kind of modification, so you may
-distribute translations of the Document under the terms of section 4.
-Replacing Invariant Sections with translations requires special
-permission from their copyright holders, but you may include
-translations of some or all Invariant Sections in addition to the
-original versions of these Invariant Sections.  You may include a
-translation of this License provided that you also include the
-original English version of this License.  In case of a disagreement
-between the translation and the original English version of this
-License, the original English version will prevail.
+The Free Software Foundation may publish new, revised versions
+of the GNU Free Documentation License from time to time.  Such new
+versions will be similar in spirit to the present version, but may
+differ in detail to address new problems or concerns. See
+<a class="url" href="http://www.gnu.org/copyleft/">http://www.gnu.org/copyleft/</a>.
+
+<P>
+Each version of the License is given a distinguishing version number.
+If the Document specifies that a particular numbered version of this
+License "or any later version" applies to it, you have the option of
+following the terms and conditions either of that specified version or
+of any later version that has been published (not as a draft) by the
+Free Software Foundation.  If the Document does not specify a version
+number of this License, you may choose any version ever published (not
+as a draft) by the Free Software Foundation.
 
 <P>
 
@@ -72,7 +78,7 @@ License, the original English version will prevail.
 <td><A HREF="node49.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
 <td><A HREF="node51.html"><img src="/python/writing/icons/next.gif"
@@ -89,11 +95,11 @@ License, the original English version will prevail.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node49.html">B..7 Aggregation With Independent</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node51.html">B..9 Termination</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node49.html">B..9 Termination</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node51.html">ADDENDUM: How to use</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node51.html

 <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN">
 <html>
 <head>
-<title>B..9 Termination</title>
-<META NAME="description" CONTENT="B..9 Termination">
+<title>ADDENDUM: How to use this License for your documents</title>
+<META NAME="description" CONTENT="ADDENDUM: How to use this License for your documents">
 <META NAME="keywords" CONTENT="zodb">
 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
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-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
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 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node52.html">
 <LINK REL="previous" HREF="node50.html">
-<LINK REL="up" HREF="node41.html">
-<LINK REL="next" HREF="node52.html">
+<LINK REL="up" HREF="node39.html">
+<LINK REL="next" href="about.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -23,10 +23,10 @@
 <td><A HREF="node50.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
-<td><A HREF="node52.html"><img src="/python/writing/icons/next.gif"
+<td><A href="about.html"><img src="/python/writing/icons/next.gif"
   border="0" height="32"
   alt="Next Page" width="32"></A></td>
 <td align="center" width="100%">ZODB/ZEO Programming Guide</td>
@@ -40,25 +40,49 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node50.html">B..8 Translation</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node52.html">B..10 Future Revisions of</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node50.html">B..10 Future Revisions of</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" href="about.html">About this document ...</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
 
-<H2><A NAME="SECTION0008100000000000000000">
-B..9 Termination</A>
+<H2><A NAME="SECTION0008120000000000000000">
+ADDENDUM: How to use this License for your documents</A>
 </H2>
 
 <P>
-You may not copy, modify, sublicense, or distribute the Document except
-as expressly provided for under this License.  Any other attempt to
-copy, modify, sublicense or distribute the Document is void, and will
-automatically terminate your rights under this License.  However,
-parties who have received copies, or rights, from you under this
-License will not have their licenses terminated so long as such
-parties remain in full compliance.
+To use this License in a document you have written, include a copy of
+the License in the document and put the following copyright and
+license notices just after the title page:
+
+<P>
+<P>
+<BLOCKQUOTE>Copyright <SPAN CLASS="MATH"><IMG
+ WIDTH="20" HEIGHT="29" ALIGN="MIDDLE" BORDER="0"
+ SRC="img1.gif"
+ ALT="$\copyright$"></SPAN> YEAR  YOUR NAME.
+      Permission is granted to copy, distribute and/or modify this document
+      under the terms of the GNU Free Documentation License, Version 1.1
+      or any later version published by the Free Software Foundation;
+      with the Invariant Sections being LIST THEIR TITLES, with the
+      Front-Cover Texts being LIST, and with the Back-Cover Texts being LIST.
+      A copy of the license is included in the section entitled ``GNU
+      Free Documentation License''.
+</BLOCKQUOTE>
+<P>
+
+<P>
+If you have no Invariant Sections, write ``with no Invariant Sections''
+instead of saying which ones are invariant.  If you have no
+Front-Cover Texts, write ``no Front-Cover Texts'' instead of
+``Front-Cover Texts being LIST''; likewise for Back-Cover Texts.
+
+<P>
+If your document contains nontrivial examples of program code, we
+recommend releasing these examples in parallel under your choice of
+free software license, such as the GNU General Public License,
+to permit their use in free software.
 
 <P>
 
@@ -69,10 +93,10 @@ parties remain in full compliance.
 <td><A HREF="node50.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
-<td><A HREF="node41.html"><img src="/python/writing/icons/up.gif"
+<td><A HREF="node39.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
-<td><A HREF="node52.html"><img src="/python/writing/icons/next.gif"
+<td><A href="about.html"><img src="/python/writing/icons/next.gif"
   border="0" height="32"
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 <td align="center" width="100%">ZODB/ZEO Programming Guide</td>
@@ -86,11 +110,11 @@ parties remain in full compliance.
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node50.html">B..8 Translation</A>
-<b class="navlabel">Up:</b> <a class="sectref" HREF="node41.html">B. GNU Free Documentation</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node52.html">B..10 Future Revisions of</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node50.html">B..10 Future Revisions of</A>
+<b class="navlabel">Up:</b> <a class="sectref" HREF="node39.html">B. GNU Free Documentation</A>
+<b class="navlabel">Next:</b> <a class="sectref" href="about.html">About this document ...</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node6.html

@@ -6,8 +6,8 @@
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-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
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@@ -15,6 +15,7 @@
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 <LINK REL="up" HREF="node2.html">
 <LINK REL="next" HREF="node7.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -97,7 +98,7 @@ suggest clarifications or additional topics, please send your comments to
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node2.html">1 Introduction</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node7.html">1.5 Acknowledgements</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node7.html

@@ -6,14 +6,15 @@
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-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="previous" HREF="node6.html">
 <LINK REL="up" HREF="node2.html">
 <LINK REL="next" HREF="node8.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -86,7 +87,7 @@ Chris McDonough, George Runyan.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node2.html">1 Introduction</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node8.html

@@ -6,8 +6,8 @@
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-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
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@@ -15,6 +15,7 @@
 <LINK REL="previous" HREF="node2.html">
 <LINK REL="up" HREF="zodb.html">
 <LINK REL="next" HREF="node9.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -70,12 +71,11 @@
 <UL>
 <LI><A href="node16.html">2.5.1 Modifying Mutable Objects</a>
 <LI><A href="node17.html">2.5.2 Some Special Methods Don't Work</a>
-<LI><A href="node18.html">2.5.3 Fixing <tt class="function">isinstance</tt> and <tt class="function">issubclass</tt></a>
-<LI><A href="node19.html">2.5.4 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
+<LI><A href="node18.html">2.5.3 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
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-<LI><A href="node20.html">2.6 Writing Persistent Classes</a>
+<LI><A href="node19.html">2.6 Writing Persistent Classes</a>
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-<LI><A href="node21.html">2.6.1 Changing Instance Attributes</a>
+<LI><A href="node20.html">2.6.1 Changing Instance Attributes</a>
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 <!--End of Table of Child-Links-->
 
@@ -107,7 +107,7 @@
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node9.html">2.1 Installing ZODB</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/node9.html

@@ -6,8 +6,8 @@
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-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
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@@ -15,6 +15,7 @@
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 <LINK REL="up" HREF="node8.html">
 <LINK REL="next" HREF="node10.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -105,7 +106,7 @@ difficulties you encounter.
 <b class="navlabel">Up:</b> <a class="sectref" HREF="node8.html">2 ZODB Programming</A>
 <b class="navlabel">Next:</b> <a class="sectref" HREF="node10.html">2.1.1 Requirements</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/zeo.html

@@ -6,27 +6,28 @@
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-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
-<LINK REL="next" HREF="node31.html">
+<LINK REL="next" HREF="node29.html">
 <LINK REL="previous" HREF="node8.html">
 <LINK REL="up" HREF="zodb.html">
-<LINK REL="next" HREF="node23.html">
+<LINK REL="next" HREF="node22.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
 <tr>
-<td><A HREF="node21.html"><img src="/python/writing/icons/previous.gif"
+<td><A HREF="node20.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
 <td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
-<td><A HREF="node23.html"><img src="/python/writing/icons/next.gif"
+<td><A HREF="node22.html"><img src="/python/writing/icons/next.gif"
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 <td align="center" width="100%">ZODB/ZEO Programming Guide</td>
@@ -40,9 +41,9 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node21.html">2.6.1 Changing Instance Attributes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node20.html">2.6.1 Changing Instance Attributes</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node23.html">3.1 How ZEO Works</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node22.html">3.1 How ZEO Works</A>
 <br><hr>
 </DIV>
 <!--End of Navigation Panel-->
@@ -59,16 +60,15 @@
 <A NAME="CHILD_LINKS"><STRONG>Subsections</STRONG></a>
 
 <UL>
-<LI><A href="node23.html">3.1 How ZEO Works</a>
-<LI><A href="node24.html">3.2 Installing ZEO</a>
+<LI><A href="node22.html">3.1 How ZEO Works</a>
+<LI><A href="node23.html">3.2 Installing ZEO</a>
 <UL>
-<LI><A href="node25.html">3.2.1 Requirements</a>
-<LI><A href="node26.html">3.2.2 Installation</a>
+<LI><A href="node24.html">3.2.1 Requirements</a>
+<LI><A href="node25.html">3.2.2 Running a server</a>
 </ul>
-<LI><A href="node27.html">3.3 Configuring and Running a ZEO Server</a>
-<LI><A href="node28.html">3.4 Testing the ZEO Installation</a>
-<LI><A href="node29.html">3.5 ZEO Programming Notes</a>
-<LI><A href="node30.html">3.6 Sample Application: chatter.py</a>
+<LI><A href="node26.html">3.3 Testing the ZEO Installation</a>
+<LI><A href="node27.html">3.4 ZEO Programming Notes</a>
+<LI><A href="node28.html">3.5 Sample Application: chatter.py</a>
 </ul>
 <!--End of Table of Child-Links-->
 
@@ -76,13 +76,13 @@
 <p><hr>
 <table align="center" width="100%" cellpadding="0" cellspacing="2">
 <tr>
-<td><A HREF="node21.html"><img src="/python/writing/icons/previous.gif"
+<td><A HREF="node20.html"><img src="/python/writing/icons/previous.gif"
   border="0" height="32"
   alt="Previous Page" width="32"></A></td>
 <td><A HREF="zodb.html"><img src="/python/writing/icons/up.gif"
   border="0" height="32"
   alt="Up One Level" width="32"></A></td>
-<td><A HREF="node23.html"><img src="/python/writing/icons/next.gif"
+<td><A HREF="node22.html"><img src="/python/writing/icons/next.gif"
   border="0" height="32"
   alt="Next Page" width="32"></A></td>
 <td align="center" width="100%">ZODB/ZEO Programming Guide</td>
@@ -96,11 +96,11 @@
   border="0" height="32"
   alt="" width="32"></td>
 </tr></table>
-<b class="navlabel">Previous:</b> <a class="sectref" HREF="node21.html">2.6.1 Changing Instance Attributes</A>
+<b class="navlabel">Previous:</b> <a class="sectref" HREF="node20.html">2.6.1 Changing Instance Attributes</A>
 <b class="navlabel">Up:</b> <a class="sectref" HREF="zodb.html">ZODB/ZEO Programming Guide</A>
-<b class="navlabel">Next:</b> <a class="sectref" HREF="node23.html">3.1 How ZEO Works</A>
+<b class="navlabel">Next:</b> <a class="sectref" HREF="node22.html">3.1 How ZEO Works</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

doc/guide/zodb/zodb.css

@@ -39,6 +39,7 @@ body                    { color: #000000;
                           background-color: #ffffff; }
 
 a:active                { color: #ff0000; }
+a[href]:hover           { background-color: #bbeeff; }
 a:visited               { color: #551a8b; }
 a:link                  { color: #0000bb; }
 
@@ -60,18 +61,30 @@ var                     { font-family: times, serif;
                           font-family: avantgarde, sans-serif;
                           font-size: 110%; }
 
+div.warning             { background-color: #fffaf0;
+                          border: thin solid black;
+                          padding: 0.5em;
+                          margin-left: 2em;
+                          margin-right: 2em; }
+
+div.warning .label      { font-size: 110%;
+                          margin-right: 0.5em; }
+
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-.verbatim               { color: #00008b;
+.verbatim pre           { color: #00008b;
                           font-family: lucida typewriter, lucidatypewriter,
-                                       monospace; }
+                                       monospace;
+                          font-size: 90%; }
+.verbatim               { margin-left: 2em; }
 
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                           margin-right: 0.5in;
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+.productions a:hover    { background-color: #99ccff; }
 .productions table      { vertical-align: baseline; }
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doc/guide/zodb/zodb.html

@@ -6,12 +6,13 @@
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 <META NAME="resource-type" CONTENT="document">
 <META NAME="distribution" CONTENT="global">
-<meta http-equiv="Content-Type" content="text/html; charset=">
-<link rel="STYLESHEET" href="zodb.css">
+<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
+<link rel="STYLESHEET" href="zodb.css" type='text/css'>
 <link rel="first" href="zodb.html">
 <link rel="contents" href="contents.html" title="Contents">
 
 <LINK REL="next" href="contents.html">
+<meta name='aesop' content='information'>
 </head>
 <body>
 <DIV CLASS="navigation">
@@ -47,8 +48,8 @@
 <h1>ZODB/ZEO Programming Guide</h1>
 <p><b><font size="+2">A.M. Kuchling</font></b></p>
 <p>akuchlin@mems-exchange.org</p>
-<p><strong>Release 0.03</strong><br>
-<strong>February 8, 2002</strong></p>
+<p><strong>Release 0.04</strong><br>
+<strong>October 4, 2002</strong></p>
 <p>
 </center>
 </div>
@@ -81,55 +82,53 @@
 <UL>
 <LI><A href="node16.html">2.5.1 Modifying Mutable Objects</a>
 <LI><A href="node17.html">2.5.2 Some Special Methods Don't Work</a>
-<LI><A href="node18.html">2.5.3 Fixing <tt class="function">isinstance</tt> and <tt class="function">issubclass</tt></a>
-<LI><A href="node19.html">2.5.4 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
+<LI><A href="node18.html">2.5.3 <tt class="method">__getattr__</tt>, <tt class="method">__delattr__</tt>, and <tt class="method">__setattr__</tt></a>
 </ul>
-<LI><A href="node20.html">2.6 Writing Persistent Classes</a>
+<LI><A href="node19.html">2.6 Writing Persistent Classes</a>
 <UL>
-<LI><A href="node21.html">2.6.1 Changing Instance Attributes</a>
+<LI><A href="node20.html">2.6.1 Changing Instance Attributes</a>
 </ul>
 </ul>
 <LI><A href="zeo.html">3 ZEO</a>
 <UL>
-<LI><A href="node23.html">3.1 How ZEO Works</a>
-<LI><A href="node24.html">3.2 Installing ZEO</a>
+<LI><A href="node22.html">3.1 How ZEO Works</a>
+<LI><A href="node23.html">3.2 Installing ZEO</a>
 <UL>
-<LI><A href="node25.html">3.2.1 Requirements</a>
-<LI><A href="node26.html">3.2.2 Installation</a>
+<LI><A href="node24.html">3.2.1 Requirements</a>
+<LI><A href="node25.html">3.2.2 Running a server</a>
 </ul>
-<LI><A href="node27.html">3.3 Configuring and Running a ZEO Server</a>
-<LI><A href="node28.html">3.4 Testing the ZEO Installation</a>
-<LI><A href="node29.html">3.5 ZEO Programming Notes</a>
-<LI><A href="node30.html">3.6 Sample Application: chatter.py</a>
+<LI><A href="node26.html">3.3 Testing the ZEO Installation</a>
+<LI><A href="node27.html">3.4 ZEO Programming Notes</a>
+<LI><A href="node28.html">3.5 Sample Application: chatter.py</a>
 </ul>
-<LI><A href="node31.html">4 Transactions and Versioning</a>
+<LI><A href="node29.html">4 Transactions and Versioning</a>
 <UL>
-<LI><A href="node32.html">4.1 Subtransactions</a>
-<LI><A href="node33.html">4.2 Undoing Changes</a>
-<LI><A href="node34.html">4.3 Versions</a>
-<LI><A href="node35.html">4.4 Multithreaded ZODB Programs</a>
+<LI><A href="node30.html">4.1 Subtransactions</a>
+<LI><A href="node31.html">4.2 Undoing Changes</a>
+<LI><A href="node32.html">4.3 Versions</a>
+<LI><A href="node33.html">4.4 Multithreaded ZODB Programs</a>
 </ul>
-<LI><A href="node36.html">5 Related Modules</a>
+<LI><A href="node34.html">5 Related Modules</a>
 <UL>
-<LI><A href="node37.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
-<LI><A href="node38.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
-<LI><A href="node39.html">5.3 B-tree Modules</a>
+<LI><A href="node35.html">5.1 <tt class="module">ZODB.PersistentMapping</tt></a>
+<LI><A href="node36.html">5.2 <tt class="module">ZODB.PersistentList</tt></a>
+<LI><A href="node37.html">5.3 BTrees Package</a>
 </ul>
-<LI><A href="node40.html">A. Resources</a>
-<LI><A href="node41.html">B. GNU Free Documentation License</a>
+<LI><A href="node38.html">A. Resources</a>
+<LI><A href="node39.html">B. GNU Free Documentation License</a>
 <UL>
-<LI><A href="node42.html">Preamble</a>
-<LI><A href="node43.html">B..1 Applicability and Definitions</a>
-<LI><A href="node44.html">B..2 Verbatim Copying</a>
-<LI><A href="node45.html">B..3 Copying in Quantity</a>
-<LI><A href="node46.html">B..4 Modifications</a>
-<LI><A href="node47.html">B..5 Combining Documents</a>
-<LI><A href="node48.html">B..6 Collections of Documents</a>
-<LI><A href="node49.html">B..7 Aggregation With Independent Works</a>
-<LI><A href="node50.html">B..8 Translation</a>
-<LI><A href="node51.html">B..9 Termination</a>
-<LI><A href="node52.html">B..10 Future Revisions of This Licence</a>
-<LI><A href="node53.html">ADDENDUM: How to use this License for your documents</a>
+<LI><A href="node40.html">Preamble</a>
+<LI><A href="node41.html">B..1 Applicability and Definitions</a>
+<LI><A href="node42.html">B..2 Verbatim Copying</a>
+<LI><A href="node43.html">B..3 Copying in Quantity</a>
+<LI><A href="node44.html">B..4 Modifications</a>
+<LI><A href="node45.html">B..5 Combining Documents</a>
+<LI><A href="node46.html">B..6 Collections of Documents</a>
+<LI><A href="node47.html">B..7 Aggregation With Independent Works</a>
+<LI><A href="node48.html">B..8 Translation</a>
+<LI><A href="node49.html">B..9 Termination</a>
+<LI><A href="node50.html">B..10 Future Revisions of This Licence</a>
+<LI><A href="node51.html">ADDENDUM: How to use this License for your documents</a>
 </ul>
 <LI><A href="about.html">About this document ...</a>
 </ul>
@@ -161,7 +160,7 @@
 </tr></table>
 <b class="navlabel">Next:</b> <a class="sectref" href="contents.html">Contents</A>
 <hr>
-<span class="release-info">Release 0.03, documentation updated on February 8, 2002.</span>
+<span class="release-info">Release 0.04, documentation updated on October 4, 2002.</span>
 </DIV>
 <!--End of Navigation Panel-->
 

src/BTrees/BTreeTemplate.c

@@ -12,7 +12,7 @@
 
  ****************************************************************************/
 
-#define BTREETEMPLATE_C "$Id: BTreeTemplate.c,v 1.71 2002/06/28 20:52:30 tim_one Exp $\n"
+#define BTREETEMPLATE_C "$Id: BTreeTemplate.c,v 1.72 2002/10/05 00:39:56 gvanrossum Exp $\n"
 
 /* Sanity-check a BTree.  This is a private helper for BTree_check.  Return:
  *      -1         Error.  If it's an internal inconsistency in the BTree,
@@ -1618,10 +1618,10 @@ static struct PyMethodDef BTree_methods[] = {
    "Return the default (or None) if the key is not found."
   },
   {"maxKey", (PyCFunction) BTree_maxKey,	METH_VARARGS,
-   "maxKey([key]) -- Fine the maximum key\n\n"
+   "maxKey([key]) -- Find the maximum key\n\n"
    "If an argument is given, find the maximum <= the argument"},
   {"minKey", (PyCFunction) BTree_minKey,	METH_VARARGS,
-   "minKey([key]) -- Fine the minimum key\n\n"
+   "minKey([key]) -- Find the minimum key\n\n"
    "If an argument is given, find the minimum >= the argument"},
   {"clear",	(PyCFunction) BTree_clear,	METH_VARARGS,
    "clear() -- Remove all of the items from the BTree"},

src/BTrees/BucketTemplate.c

@@ -12,7 +12,7 @@
 
  ****************************************************************************/
 
-#define BUCKETTEMPLATE_C "$Id: BucketTemplate.c,v 1.47 2002/06/27 22:09:32 tim_one Exp $\n"
+#define BUCKETTEMPLATE_C "$Id: BucketTemplate.c,v 1.48 2002/10/05 00:39:56 gvanrossum Exp $\n"
 
 /* Use BUCKET_SEARCH to find the index at which a key belongs.
  * INDEX    An int lvalue to hold the index i such that KEY belongs at
@@ -1305,10 +1305,10 @@ static struct PyMethodDef Bucket_methods[] = {
   {"__init__",	(PyCFunction) Mapping_update,	METH_VARARGS,
    "__init__(collection) -- Initialize with items from the given collection"},
   {"maxKey", (PyCFunction) Bucket_maxKey,	METH_VARARGS,
-   "maxKey([key]) -- Fine the maximum key\n\n"
+   "maxKey([key]) -- Find the maximum key\n\n"
    "If an argument is given, find the maximum <= the argument"},
   {"minKey", (PyCFunction) Bucket_minKey,	METH_VARARGS,
-   "minKey([key]) -- Fine the minimum key\n\n"
+   "minKey([key]) -- Find the minimum key\n\n"
    "If an argument is given, find the minimum >= the argument"},
   {"values",	(PyCFunction) bucket_values,	METH_VARARGS,
      "values([min, max]) -- Return the values"},

src/BTrees/SetTemplate.c

@@ -12,7 +12,7 @@
   
  ****************************************************************************/
 
-#define SETTEMPLATE_C "$Id: SetTemplate.c,v 1.15 2002/02/21 21:41:17 jeremy Exp $\n"
+#define SETTEMPLATE_C "$Id: SetTemplate.c,v 1.16 2002/10/05 00:39:57 gvanrossum Exp $\n"
 
 static PyObject *
 Set_insert(Bucket *self, PyObject *args)
@@ -152,10 +152,10 @@ static struct PyMethodDef Set_methods[] = {
   {"clear",	(PyCFunction) bucket_clear,	METH_VARARGS,
    "clear() -- Remove all of the items from the bucket"},
   {"maxKey", (PyCFunction) Bucket_maxKey,	METH_VARARGS,
-   "maxKey([key]) -- Fine the maximum key\n\n"
+   "maxKey([key]) -- Find the maximum key\n\n"
    "If an argument is given, find the maximum <= the argument"},
   {"minKey", (PyCFunction) Bucket_minKey,	METH_VARARGS,
-   "minKey([key]) -- Fine the minimum key\n\n"
+   "minKey([key]) -- Find the minimum key\n\n"
    "If an argument is given, find the minimum >= the argument"},
 #ifdef PERSISTENT
   {"_p_resolveConflict", (PyCFunction) bucket__p_resolveConflict, METH_VARARGS,

src/BTrees/TreeSetTemplate.c

@@ -12,7 +12,7 @@
 
  ****************************************************************************/
 
-#define TREESETTEMPLATE_C "$Id: TreeSetTemplate.c,v 1.14 2002/06/19 23:44:20 tim_one Exp $\n"
+#define TREESETTEMPLATE_C "$Id: TreeSetTemplate.c,v 1.15 2002/10/05 00:39:57 gvanrossum Exp $\n"
 
 static PyObject *
 TreeSet_insert(BTree *self, PyObject *args)
@@ -99,10 +99,10 @@ static struct PyMethodDef TreeSet_methods[] = {
   {"keys",	(PyCFunction) BTree_keys,	METH_VARARGS,
      "keys() -- Return the keys"},
   {"maxKey", (PyCFunction) BTree_maxKey,	METH_VARARGS,
-   "maxKey([key]) -- Fine the maximum key\n\n"
+   "maxKey([key]) -- Find the maximum key\n\n"
    "If an argument is given, find the maximum <= the argument"},
   {"minKey", (PyCFunction) BTree_minKey,	METH_VARARGS,
-   "minKey([key]) -- Fine the minimum key\n\n"
+   "minKey([key]) -- Find the minimum key\n\n"
    "If an argument is given, find the minimum >= the argument"},
   {"clear",	(PyCFunction) BTree_clear,	METH_VARARGS,
    "clear() -- Remove all of the items from the BTree"},

src/ZEO/ClientStorage.py

@@ -20,7 +20,7 @@ ClientStorageError -- exception raised by ClientStorage
 UnrecognizedResult -- exception raised by ClientStorage
 ClientDisconnected -- exception raised by ClientStorage
 
-$Id: ClientStorage.py,v 1.74 2002/10/04 16:46:23 gvanrossum Exp $
+$Id: ClientStorage.py,v 1.75 2002/10/05 00:35:25 gvanrossum Exp $
 """
 
 # XXX TO DO
@@ -88,6 +88,8 @@ class DisconnectedServerStub:
 # Singleton instance of DisconnectedServerStub
 disconnected_stub = DisconnectedServerStub()
 
+MB = 1024**2
+
 class ClientStorage:
 
     """A Storage class that is a network client to a remote storage.
@@ -105,7 +107,7 @@ class ClientStorage:
     ConnectionManagerClass = ConnectionManager
     StorageServerStubClass = ServerStub.StorageServer
 
-    def __init__(self, addr, storage='1', cache_size=20000000,
+    def __init__(self, addr, storage='1', cache_size=20 * MB,
                  name='', client=None, debug=0, var=None,
                  min_disconnect_poll=5, max_disconnect_poll=300,
                  wait_for_server_on_startup=None, # deprecated alias for wait
@@ -120,15 +122,16 @@ class ClientStorage:
         Arguments:
 
         addr -- The server address(es).  This is either a list of
-            addresses, or a single address.  Each address can be a
-            (hostname, port) tuple to signify a TCP/IP connection, or
+            addresses or a single address.  Each address can be a
+            (hostname, port) tuple to signify a TCP/IP connection or
             a pathname string to signify a Unix domain socket
             connection.  A hostname may be a DNS name or a dotted IP
             address.  Required.
 
-        storage -- The storage name, defaulting to '1'.  This must
+        storage -- The storage name, defaulting to '1'.  The name must
             match one of the storage names supported by the server(s)
-            specified by the addr argument.
+            specified by the addr argument.  The storage name is
+            displayed in the Zope control panel.
 
         cache_size -- The disk cache size, defaulting to 20 megabytes.
             This is passed to the ClientCache constructor.
@@ -137,16 +140,15 @@ class ClientStorage:
             str(addr) is used as the storage name.
 
         client -- The client name, defaulting to None.  If this is
-            false, the environment value ZEO_CLIENT is used.  if the
+            false, the environment value ZEO_CLIENT is used.  If the
             effective value is true, the client cache is persistent.
             See ClientCache for more info.
 
         debug -- Ignored.  This is present only for backwards
             compatibility with ZEO 1.
 
-        var -- The 'var' directory, defaulting to None.  This is
-            passed to the ClientCache constructor, which picks a
-            default if the value is None.
+        var -- The 'var' directory, defaulting to None, in which
+            the persistent cache files should be written.
 
         min_disconnect_poll -- The minimum delay in seconds between
             attempts to connect to the server, in seconds.  Defaults

src/ZEO/__init__.py

@@ -21,4 +21,4 @@ ZEO's home on the web is
 
 """
 
-version = "2.0b1"
+version = "2.0b2"

src/ZEO/tests/testZEO.py

@@ -26,6 +26,7 @@ import unittest
 import zLOG
 
 # ZODB test support
+import ZODB
 from ZODB.tests.MinPO import MinPO
 from ZODB.tests.StorageTestBase import zodb_unpickle
 
@@ -130,6 +131,16 @@ class GenericTests(
         self._storage.close()
         self._storage = ClientStorage(addr, read_only=read_only, wait=1)
 
+    def checkWriteMethods(self):
+        # ReadOnlyStorage defines checkWriteMethods.  The decision
+        # about where to raise the read-only error was changed after
+        # Zope 2.5 was released.  So this test needs to detect Zope
+        # of the 2.5 vintage and skip the test.
+
+        # The __version__ attribute was not present in Zope 2.5.
+        if hasattr(ZODB, "__version__"):
+            ReadOnlyStorage.ReadOnlyStorage.checkWriteMethods(self)
+
 class UnixTests(GenericTests):
 
     """Add Unix-specific scaffolding to the generic test suite."""

src/ZEO/version.txt

-2.0b1
+2.0b2
 

src/ZODB/__init__.py

@@ -12,7 +12,7 @@
 #
 ##############################################################################
 
-__version__ = '3.1b1+'
+__version__ = '3.1b2'
 
 import sys
 import cPersistence, Persistence