X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;ds=sidebyside;f=m4%2Ffpurge.m4;h=234f563f864739338f8e66e95c93ae38c4919e5d;hb=ae006b4;hp=2de2179696dfa7a8b5b2d73fdbb8623c31218bb0;hpb=92b81629ca04421e908119a7e93510dab499f3ae;p=gnulib.git

diff --git a/m4/fpurge.m4 b/m4/fpurge.m4
index 2de217969..234f563f8 100644
--- a/m4/fpurge.m4
+++ b/m4/fpurge.m4
@@ -1,16 +1,45 @@
-# fpurge.m4 serial 1
-dnl Copyright (C) 2007 Free Software Foundation, Inc.
+# fpurge.m4 serial 7
+dnl Copyright (C) 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,
 dnl with or without modifications, as long as this notice is preserved.
 
 AC_DEFUN([gl_FUNC_FPURGE],
 [
+  AC_REQUIRE([gl_STDIO_H_DEFAULTS])
   AC_CHECK_FUNCS_ONCE([fpurge])
   AC_CHECK_FUNCS_ONCE([__fpurge])
-  AC_CHECK_DECLS([fpurge], , , [#include <stdio.h>])
-  if test $ac_cv_func_fpurge = no && test $ac_cv_func___fpurge = no; then
-    AC_LIBOBJ([fpurge])
-    AC_CHECK_FUNCS([fpurge])
+  AC_CHECK_DECLS([fpurge], , , [[#include <stdio.h>]])
+  if test "x$ac_cv_func_fpurge" = xyes; then
+    HAVE_FPURGE=1
+    # Detect BSD bug.  Only cygwin 1.7 is known to be immune.
+    AC_CACHE_CHECK([whether fpurge works], [gl_cv_func_fpurge_works],
+      [AC_RUN_IFELSE([AC_LANG_PROGRAM([[#include <stdio.h>
+]], [FILE *f = fopen ("conftest.txt", "w+");
+        if (!f) return 1;
+        if (fputc ('a', f) != 'a') return 2;
+        rewind (f);
+        if (fgetc (f) != 'a') return 3;
+        if (fgetc (f) != EOF) return 4;
+        if (fpurge (f) != 0) return 5;
+        if (putc ('b', f) != 'b') return 6;
+        if (fclose (f) != 0) return 7;
+        if ((f = fopen ("conftest.txt", "r")) == NULL) return 8;
+        if (fgetc (f) != 'a') return 9;
+        if (fgetc (f) != 'b') return 10;
+        if (fgetc (f) != EOF) return 11;
+        if (fclose (f) != 0) return 12;
+        if (remove ("conftest.txt") != 0) return 13;
+        return 0;])],
+      [gl_cv_func_fpurge_works=yes], [gl_cv_func_fpurge_works=no],
+      [gl_cv_func_fpurge_works='guessing no'])])
+    if test "x$gl_cv_func_fpurge_works" != xyes; then
+      REPLACE_FPURGE=1
+    fi
+  else
+    HAVE_FPURGE=0
+  fi
+  if test "x$ac_cv_have_decl_fpurge" = xno; then
+    HAVE_DECL_FPURGE=0
   fi
 ])