update NEWS.stable

[gnulib.git] / m4 / dup2.m4

diff --git a/m4/dup2.m4 b/m4/dup2.m4
index def263b..5c2cc96 100644 (file)
--- a/m4/dup2.m4
+++ b/m4/dup2.m4
@@ -1,4 +1,4 @@
-#serial 12
+#serial 14
 dnl Copyright (C) 2002, 2005, 2007, 2009-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -8,24 +8,28 @@ AC_DEFUN([gl_FUNC_DUP2],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
   AC_REQUIRE([AC_CANONICAL_HOST])
-  AC_CHECK_FUNCS_ONCE([dup2 fcntl])
-  if test $ac_cv_func_dup2 = no; then
-    HAVE_DUP2=0
-    AC_LIBOBJ([dup2])
-  else
+  m4_ifdef([gl_FUNC_DUP2_OBSOLETE], [
+    AC_CHECK_FUNCS_ONCE([dup2])
+    if test $ac_cv_func_dup2 = no; then
+      HAVE_DUP2=0
+    fi
+  ], [
+    AC_DEFINE([HAVE_DUP2], [1], [Define to 1 if you have the 'dup2' function.])
+  ])
+  if test $HAVE_DUP2 = 1; then
     AC_CACHE_CHECK([whether dup2 works], [gl_cv_func_dup2_works],
       [AC_RUN_IFELSE([
          AC_LANG_PROGRAM([[#include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>]],
            [int result = 0;
-#if HAVE_FCNTL
+#ifdef FD_CLOEXEC
             if (fcntl (1, F_SETFD, FD_CLOEXEC) == -1)
               result |= 1;
-#endif HAVE_FCNTL
+#endif
             if (dup2 (1, 1) == 0)
               result |= 2;
-#if HAVE_FCNTL
+#ifdef FD_CLOEXEC
             if (fcntl (1, F_GETFD) != FD_CLOEXEC)
               result |= 4;
 #endif
@@ -55,16 +59,15 @@ AC_DEFUN([gl_FUNC_DUP2],
          esac])
       ])
     if test "$gl_cv_func_dup2_works" = no; then
-      gl_REPLACE_DUP2
+      REPLACE_DUP2=1
     fi
   fi
-])
-
-AC_DEFUN([gl_REPLACE_DUP2],
-[
-  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
-  if test $ac_cv_func_dup2 = yes; then
-    REPLACE_DUP2=1
-  fi
-  AC_LIBOBJ([dup2])
+  dnl Replace dup2() for supporting the gnulib-defined fchdir() function,
+  dnl to keep fchdir's bookkeeping up-to-date.
+  m4_ifdef([gl_FUNC_FCHDIR], [
+    gl_TEST_FCHDIR
+    if test $HAVE_FCHDIR = 0; then
+      REPLACE_DUP2=1
+    fi
+  ])
 ])