need to include string.h for strdup()

From: Bryan Henderson <bryanh@giraffe-data.com>

Comment-out dynamic link function declarations since they are all
 provided by the system.
Should we bother continuing to support non-elf Linux systems??

Change declarations from "struct varlena *" to "text *".
Remove register variables since compiler should do better on its own.

Change NOTICE/NOTICE/NOTICE/WARN elog messages to a single message
 with a few newline/tab breaks embedded in the string. Much cleaner I hope.

 closer to standard behavior.
Substitute "text *" for "struct varlena *" in declarations.

 sigsetjmp as a macro, so gives compiler warning without bracketing.

From: Ryan Kirkpatrick <rkirkpat@nag.cs.colorado.edu>

From: Ryan Kirkpatrick <rkirkpat@nag.cs.colorado.edu>

  o  A new patch that contains the following changes:
        -- The pg_pwd file is now cached in the postmaster's memory.
        -- pg_pwd is reloaded when the postmaster detects a flag file creat()'ed
           by a backend.
        -- qsort() is used to sort loaded password entries, and bsearch() is
           is used to find entries in the pg_pwd cache.
        -- backends now copy the pg_user relation to pg_pwd.pid, and then
           rename the temp file to be pg_pwd.
        -- The delimiter for pg_pwd has been changed to a tab character.

PORTNAME should not be used anywhere anymore...I hope :)

                                  ^^^^ gcc likes this

Add unionall boolean field to SubSelect structure.

 (> 16 characters) are allowed in pg_proc (thanks Bruce!).

Add non-working code which is commented-out to copy GroupClause structures.

 and from SELECT ... INTO ... support code.
Allow NOT, IS NULL, IS NOT NULL in constraints.
Define unionall boolean flag in SubSelect structure.
Implement row descriptors: (a, b, c) = (x, y, z).
Change IS TRUE, IS FALSE, etc. to expressions using "=" rather than
 function calls to istrue() or isfalse() to allow optimization.
Force type for TRUE and FALSE to bool.

Add a few lines of test code playing with the unique flag for unions.
 Does not do much helpful yet.

 is legal. Fix a little whitespace in other declarations.

 names over 16 characters. datet_datetime() -> datetime_datetime(), etc.