Fix -p function and Fcntl::S_IFIFO constant under Microsoft VC compiler

Create S_IFIFO macro as an alias for _S_IFIFO if only the latter is being
defined by the standard headers (e.g. Microsoft Visual C++).

This is necessary to get the C<-p> function working, and also to define
the Fcntl::S_IFIFO constant.

See also http://bugs.activestate.com/show_bug.cgi?id=82665

Cheers,
-Jan

From 6386a37b103723e3c473119b95dd0b8edc59a1ed Mon Sep 17 00:00:00 2001
From: Jan Dubois <jand@activestate.com>
Date: Mon, 27 Apr 2009 15:44:23 -0700
Subject: [PATCH] Create S_IFIFO macro as an alias for _S_IFIFO if only the latter is being
 defined by the standard headers (e.g. Microsoft Visual C++).

This is necessary to get the C<-p> function working, and also to define
the Fcntl::S_IFIFO constant.

See also http://bugs.activestate.com/show_bug.cgi?id=82665

Signed-off-by: H.Merijn Brand <h.m.brand@xs4all.nl>

perl.h

@@ -1143,6 +1143,13 @@ EXTERN_C int usleep(unsigned int);
 #   include <sys/stat.h>
 #endif
 
+/* Microsoft VC's sys/stat.h defines all S_Ixxx macros except S_IFIFO.
+   This definition should ideally go into win32/win32.h, but S_IFIFO is
+   used later here in perl.h before win32/win32.h is being included. */
+#if !defined(S_IFIFO) && defined(_S_IFIFO)
+#   define S_IFIFO _S_IFIFO
+#endif
+
 /* The stat macros for Amdahl UTS, Unisoft System V/88 (and derivatives
    like UTekV) are broken, sometimes giving false positives.  Undefine
    them here and let the code below set them to proper values.

pod/perlport.pod

@@ -1600,9 +1600,11 @@ C<-x>, C<-o>. (S<Mac OS>, Win32, VMS, S<RISC OS>)
 C<-b>, C<-c>, C<-k>, C<-g>, C<-p>, C<-u>, C<-A> are not implemented.
 (S<Mac OS>)
 
-C<-g>, C<-k>, C<-l>, C<-p>, C<-u>, C<-A> are not particularly meaningful.
+C<-g>, C<-k>, C<-l>, C<-u>, C<-A> are not particularly meaningful.
 (Win32, VMS, S<RISC OS>)
 
+C<-p> is not particularly meaningful. (VMS, S<RISC OS>)
+
 C<-d> is true if passed a device spec without an explicit directory.
 (VMS)