Adding new fields Last_{IO,SQL}_Errno and Last_{IO,SQL}_Error to output
of SHOW SLAVE STATUS to hold errors from I/O and SQL thread respectively.
Old fields Last_Error and Last_Errno are aliases for Last_SQL_Error and
Last_SQL_Errno respectively.

Fields are added last to output of SHOW SLAVE STATUS to allow old applications
to use the same positional arguments into the row, while allowing new
application to benefit from the added information.

In addition, some new error codes are added (especially for the I/O
thread) to be able to provide sensible error message.

into  romeo.(none):/home/bkroot/mysql-5.1-new-rpl

into  mysql.com:/home/bk/MERGE/mysql-5.1-merge

into  mysql.com:/home/bk/MERGE/mysql-5.0-merge

into  mysql.com:/home/bk/MERGE/mysql-5.1-merge

into  mysql.com:/home/bk/MERGE/mysql-5.0-merge

into  mysql.com:/home/bk/MERGE/mysql-4.1-merge

into  quant.(none):/ext/mysql/bk/mysql-5.0-bug24507

into  mysql.com:/usr/home/bar/mysql-5.1.b20396

into  mysql.com:/usr/home/bar/mysql-5.0.b24158

into  quant.(none):/ext/mysql/bk/mysql-5.0-bug24507

The problem was located to lie inside current NPTL pthread_exit() 
implementation. Race conditions in this code can lead to segmentation
fault. Hovewer, this can happen only in a race between first thread 
calling pthread_exit() and other threads. 

Workaround implemented in this patch spawns a dummy thread, which
exits immediately, during thread lib initialization. This will exclude
segment violations when further threads exit.
 

into  mysql.com:/usr/home/bar/mysql-5.0.b20396

into  suse.vabb.com:/home/Chuck/development/mysql-5.1_WL_3618

Please see worklog for details on files changed.

into  example.com:/work/mysql-5.1-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-5.1-maint

Remove DBUG_ENTER in my_end

uninitialized list of guarded instances.

into  neptunus.(none):/home/msvensson/mysql/mysql-5.1-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-5.0-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-5.1-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-5.0-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-4.1-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-5.1-maint

into  neptunus.(none):/home/msvensson/mysql/mysql-5.1

into  rolltop.ignatz42.dyndns.org:/mnt/storeage/mysql-5.0-maint

into  rolltop.ignatz42.dyndns.org:/mnt/storeage/mysql-5.1-maint