which is used by Barry's new LockFile class.  The effect of leaving
regions of a file locked when closing the file, or when exiting the
process, is undefined on Windows, and the new scheme restricts itself
to operations with defined semantics.

encapsulation the storage lock file.

unlock_file() call which awaits Tim's backport of
winlock.UnlockFile().  This is no-op on *nix.

Also, implement a better API for dealing with lock files.  Use the
LockFile class for clean acquisition and release of locks, and
unlinking of lock files.

- add missing period

- normalize some markup usage

- fix lots of typos

types that grow an __module__ in future versions of Python.

- minor cleanup

reconsidered.  That's for another day, though.

- use constant from errno module instead of magic number

    Needed since we're not actually waiting for the ZEO server process
    to exit (it's a grandchild, not a child).  It we don't wait,
    there's a race condition between one test and the next -- if the
    ZEO server isn't done shutting down, the database may still be
    locked when the next test starts.

it just uses the gzip module's default compression level (i.e. 9).

No need to specify -z on recovery because the script will
automatically uncompress gzip'd files.  It does this by looking at the
file extension, which will be .fsz or .deltafsz for compressed files.

incremental instead of all the incrementals.  Less assured consistency
but much less disk i/o.

saving state in a pck pickle file, and doing an incremental parse the
next time.  Specifically:

Added -f and -r flags.  The -f flag points to the pickle state file
(by default ./zeoqueue.pck).  The -r flag simply removes this file.
This is useful for log rotation in the cron job, and yes rm would have
been fine, but this option was requested by customers.

process_file(): Added to Status class so that the processing is done
here, where we can seek to a stored file position.

Also added the secret -0 option for testing, which suppresses the file
position seek (useful when the log file is split into chunks).

Return the number of blocked clients as the exit status code.

Also, avoid storing wrappers.

Added a module docstring as a usage() string.  Also add --help/-h.

Rewrote two of the regexps as verbose re's for readability <wink>.
Use named groups.

Use True/False where appropriate.

Txn: Added a `voters' attribute which is a list of clients seen doing
a vote.  This is cleared on abort or finish.  Thus if we see a
transaction with a non-empty voters list, we know that that
transaction was blocked and it was the first voter that grabbed the
lock.  This client (as an address) is displayed in the report.

call_*(): Pass the client address into the call, as grep'd out of the
zrpc-conn part of the line.  Only call_tpc_vote() really cares about
this.

Most controversial: process the entire file, line by line.
Alternatives, if necessary:
    - go back to the original progressive skip backwards approach
    - add an incremental reader (recording file positions)
    - use as a filter

iterator() method.

BaseStorage's copyTransactionsFrom() method's "other" argument.

since the last call may have left us with an invalid index.  Raise
RuntimeError instead of segfaulting (or picking up random trash) if so.
A new (and previously segfaulting) test case is courtesy of Steve
Alexander.

by Barry Warsaw.

package.

meaningfully used the way the config schema currently defines the
field, so remove it.

Document the remaining settings for filestorage.

meaningfully used the way the config schema currently defines the
field, so remove it.

checkNoVerificationOnServerRestartWith2Clients(): Pass perstorage to
pollUp(), which should eliminate the None != 'no verification'
failures.

so we're consistent with the cleanup that tpc_abort() does.

Re-enable these tests; I can't reproduce the claimed breakage in the
Zope 2.7 tree.

comment describing Jim's desire to reach into ZConfig to decide
whether we should enter the hosed state or not.

we should eventually hook this into ZConfig.