X-Git-Url: http://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Flseek.m4;h=86db59ecdc064d7c231e9f08f12944a19c84af8e;hb=0491c1244075391cb114940990fa85afd28d54af;hp=f3084957c186bbac4bc6f4f398a15f5200add6a3;hpb=b2e2010c7c902235b5efb5bd3c6529f61b093aa4;p=gnulib.git

diff --git a/m4/lseek.m4 b/m4/lseek.m4
index f3084957c..86db59ecd 100644
--- a/m4/lseek.m4
+++ b/m4/lseek.m4
@@ -1,5 +1,5 @@
-# lseek.m4 serial 4
-dnl Copyright (C) 2007, 2009, 2010 Free Software Foundation, Inc.
+# lseek.m4 serial 8
+dnl Copyright (C) 2007, 2009-2012 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.
@@ -8,43 +8,41 @@ AC_DEFUN([gl_FUNC_LSEEK],
 [
   AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
   AC_REQUIRE([AC_PROG_CC])
+  AC_CHECK_HEADERS_ONCE([unistd.h])
   AC_CACHE_CHECK([whether lseek detects pipes], [gl_cv_func_lseek_pipe],
     [if test $cross_compiling = no; then
-       AC_LINK_IFELSE([
+       AC_LINK_IFELSE([AC_LANG_PROGRAM([[
 #include <sys/types.h> /* for off_t */
 #include <stdio.h> /* for SEEK_CUR */
-#include <unistd.h>
-int main ()
-{
+#if HAVE_UNISTD_H
+# include <unistd.h>
+#else /* on Windows with MSVC */
+# include <io.h>
+#endif
+]], [[
   /* Exit with success only if stdin is seekable.  */
   return lseek (0, (off_t)0, SEEK_CUR) < 0;
-}],
+]])],
          [if test -s conftest$ac_exeext \
              && ./conftest$ac_exeext < conftest.$ac_ext \
-             && { echo hi | ./conftest$ac_exeext; test $? = 1; }; then
+             && test 1 = "`echo hi \
+               | { ./conftest$ac_exeext; echo $?; cat >/dev/null; }`"; then
             gl_cv_func_lseek_pipe=yes
           else
             gl_cv_func_lseek_pipe=no
           fi],
          [gl_cv_func_lseek_pipe=no])
      else
-       AC_COMPILE_IFELSE([
+       AC_COMPILE_IFELSE([AC_LANG_SOURCE([[
 #if ((defined _WIN32 || defined __WIN32__) && ! defined __CYGWIN__) || defined __BEOS__
 /* mingw and BeOS mistakenly return 0 when trying to seek on pipes.  */
   Choke me.
-#endif],
+#endif]])],
          [gl_cv_func_lseek_pipe=yes], [gl_cv_func_lseek_pipe=no])
      fi])
   if test $gl_cv_func_lseek_pipe = no; then
-    gl_REPLACE_LSEEK
+    REPLACE_LSEEK=1
+    AC_DEFINE([LSEEK_PIPE_BROKEN], [1],
+      [Define to 1 if lseek does not detect pipes.])
   fi
 ])
-
-AC_DEFUN([gl_REPLACE_LSEEK],
-[
-  AC_LIBOBJ([lseek])
-  AC_REQUIRE([gl_UNISTD_H_DEFAULTS])
-  REPLACE_LSEEK=1
-  AC_DEFINE([LSEEK_PIPE_BROKEN], [1],
-            [Define to 1 if lseek does not detect pipes.])
-])