Proposed replacement for pipe under Win32

To go in src/port/ directory.

This is to allow the handles returned by pipe to be used in select() calls
(which Win32 doesn't allow with the native pipe() call), thereby obviating
the need for reworking of the select() mechanisms in pgstat.c.

Additionally, something of the sort would be required at the top of pgstat.c

#ifdef WIN32
#define pipe(a) pgpipe(a)
#define write(a,b,c) send(a,b,c,0)
#define read(a,b,c) recv(a,b,c,0)
#endif

For reference, see this thread:
http://archives.postgresql.org/pgsql-hackers/2003-12/msg00650.php

Cheers,
Claudio

---
Certain disclaimers and policies apply to all email sent from Memetrics.
For the full text of these disclaimers and policies see
<a
href="http://www.memetrics.com/emailpolicy.html">http://www.memetrics.com/em
ailpolicy.html</a>