need to be created by hand anymore.

the 7.3 branch as well as later branches ... so no need to update
manually.

and VACUUM: in the interval between adding a new page to the relation
and formatting it, it was possible for VACUUM to come along and decide
it should format the page too.  Though not harmful in itself, this would
cause data loss if a third transaction were able to insert tuples into
the vacuumed page before the original extender got control back.

before we check commit/abort status.  Formerly this was done in some paths
but not all, with the result that a transaction might be considered
committed for some purposes before it became committed for others.
Per example found by Jan Wieck.

is a way to recover from disabling connections to all databases at once.

output area as INTERNAL not CSTRING.  This is to prevent people from
calling the functions by hand.  This is a permanent solution for the
back branches but I hope it is just a stopgap for HEAD.

a warning when a variable is used as a format string for printf()
and similar functions (if the variable is derived from untrusted
data, it could include unexpected formatting sequences). This
emits too many warnings to be enabled by default, but it does
flag a few dubious constructs in the Postgres tree. This patch
fixes up the obvious variants: functions that are passed a variable
format string but no additional arguments.

This patch fixes a bug in pg_dump (triggers with formatting sequences
in their names are not dumped correctly) and some related pg_dump
code that looks dubious; cleanups for more harmless instances have
been applied to more recent branches.

incorrect -F argument: write_msg() expects its first parameter to be a
"module name", not the format string.