This is obsolete and doesn't work anymore.

contrib/unixdate/Makefile

-#
-# $Header: /cvsroot/pgsql/contrib/unixdate/Attic/Makefile,v 1.3 2000/07/09 13:13:50 petere Exp $
-#
-
-subdir = contrib/unixdate
-top_builddir = ../..
-include ../../src/Makefile.global
-
-all:
-
-install: installdirs
-	$(INSTALL_DATA) unixdate.sql $(datadir)/contrib
-
-uninstall:
-	rm -f $(datadir)/contrib/unixdate.sql
-
-installdirs:
-	$(mkinstalldirs) $(datadir)/contrib

contrib/unixdate/unixdate.sql

--- unixdate
--- Routines to convert int4 (Unix system time) to datetime
---  and int4 (delta time in seconds) to timespan
---
--- Thomas Lockhart (lockhart@alumni.caltech.edu)
--- 1997-11-25
---
--- This cheats and reuses existing code in the standard package.
--- Can not include this directly because built-in functions are optimized
---  into a cache and the duplicate function names abstime_datetime() and
---  reltime_timespan() would result in duplicate constants.
---
--- This works with Postgres v6.2 and higher.
-
---
--- Conversions from integer to datetime
---
-
-CREATE FUNCTION abstime_datetime(int4)
- RETURNS datetime
- AS '-' LANGUAGE 'internal';
-
-CREATE FUNCTION datetime(int4)
- RETURNS datetime
- AS 'select abstime_datetime($1)' LANGUAGE 'SQL';
-
-CREATE FUNCTION reltime_timespan(int4)
- RETURNS timespan
- AS '-' LANGUAGE 'internal';
-
-CREATE FUNCTION timespan(int4)
- RETURNS timespan
- AS 'select reltime_timespan($1)' LANGUAGE 'SQL';
-