From: Eric Blake <ebb9@byu.net>
Date: Wed, 6 Jan 2010 21:12:45 +0000 (-0700)
Subject: pread: fix compilation on glibc
X-Git-Url: https://pintos-os.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=978114f6f3d4c5d0c1fd7f2bb1f48a37bab89553;p=pspp

pread: fix compilation on glibc

pread was not mandatory until POSIX 2008, so glibc does not
expose it by default.

* m4/pread.m4 (gl_FUNC_PREAD): Request all interfaces.
Reported by Ralf Wildenhues.

Signed-off-by: Eric Blake <ebb9@byu.net>
---

diff --git a/ChangeLog b/ChangeLog
index 7b9dc990fc..3e3f70bf13 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2010-01-06  Eric Blake  <ebb9@byu.net>
 
+	pread: fix compilation on glibc
+	* m4/pread.m4 (gl_FUNC_PREAD): Request all interfaces.
+	Reported by Ralf Wildenhues.
+
 	dirent: fix test failure
 	* lib/dirent.in.h (includes): Guarantee ino_t.
 	Reported by Ralf Wildenhues.
diff --git a/m4/pread.m4 b/m4/pread.m4
index 50d9e4d997..f1425a6b1d 100644
--- a/m4/pread.m4
+++ b/m4/pread.m4
@@ -1,4 +1,4 @@
-# pread.m4 serial 1
+# pread.m4 serial 2
 dnl Copyright (C) 2009-2010 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -7,6 +7,9 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_PREAD],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
+  dnl Persuade glibc <unistd.h> to declare pread().
+  AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
   AC_CHECK_FUNCS_ONCE([pread])
   if test $ac_cv_func_pread = no; then
     HAVE_PREAD=0