X-Git-Url: https://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Ffdatasync.m4;h=551c0d9ff4e0d57afe12f6d69f7784774df56984;hb=8e0f64e4cd12f7779113bc438afd106dad3e1f1a;hp=8eceeb547bcc2f64d3178780795187160d04e483;hpb=64da7b6c00400c0a5e5b02df98faec97c0954a3c;p=gnulib.git

diff --git a/m4/fdatasync.m4 b/m4/fdatasync.m4
index 8eceeb547..551c0d9ff 100644
--- a/m4/fdatasync.m4
+++ b/m4/fdatasync.m4
@@ -1,5 +1,5 @@
-# fdatasync.m4 serial 1
-dnl Copyright (C) 2008-2011 Free Software Foundation, Inc.
+# fdatasync.m4 serial 4
+dnl Copyright (C) 2008-2013 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
@@ -7,8 +7,26 @@ dnl with or without modifications, as long as this notice is preserved.
 AC_DEFUN([gl_FUNC_FDATASYNC],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
-  AC_CHECK_FUNCS_ONCE([fdatasync])
-  if test $ac_cv_func_fdatasync = no; then
-    HAVE_FDATASYNC=0
+
+  dnl Using AC_CHECK_FUNCS_ONCE would break our subsequent AC_SEARCH_LIBS
+  AC_CHECK_DECLS_ONCE([fdatasync])
+  LIB_FDATASYNC=
+  AC_SUBST([LIB_FDATASYNC])
+
+  if test $ac_cv_have_decl_fdatasync = no; then
+    HAVE_DECL_FDATASYNC=0
+    dnl Mac OS X 10.7 has fdatasync but does not declare it.
+    AC_CHECK_FUNCS([fdatasync])
+    if test $ac_cv_func_fdatasync = no; then
+      HAVE_FDATASYNC=0
+    fi
+  else
+    dnl Solaris <= 2.6 has fdatasync() in libposix4.
+    dnl Solaris 7..10 has it in librt.
+    gl_saved_libs=$LIBS
+    AC_SEARCH_LIBS([fdatasync], [rt posix4],
+                   [test "$ac_cv_search_fdatasync" = "none required" ||
+                    LIB_FDATASYNC=$ac_cv_search_fdatasync])
+    LIBS=$gl_saved_libs
   fi
 ])