X-Git-Url: https://erislabs.net/gitweb/?a=blobdiff_plain;f=m4%2Funlocked-io.m4;h=c536d2dd9377ea87f529e2ca30a6e9f1e64fe68f;hb=44d7c1c1f004fa9bfb8ec3948de2671a7958cf5b;hp=cd1c5f4ef7393da670629b9525f4eaa4d700fa8b;hpb=23fe10e274cf20fb2cb75ea1da9556a733106657;p=gnulib.git

diff --git a/m4/unlocked-io.m4 b/m4/unlocked-io.m4
index cd1c5f4ef..c536d2dd9 100644
--- a/m4/unlocked-io.m4
+++ b/m4/unlocked-io.m4
@@ -1,4 +1,11 @@
-#serial 9
+# unlocked-io.m4 serial 11
+
+# Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software
+# Foundation, Inc.
+#
+# This file is free software; the Free Software Foundation
+# gives unlimited permission to copy and/or distribute it,
+# with or without modifications, as long as this notice is preserved.
 
 dnl From Jim Meyering.
 dnl
@@ -10,6 +17,11 @@ dnl on Solaris 2.6).
 
 AC_DEFUN([gl_FUNC_GLIBC_UNLOCKED_IO],
 [
+  AC_DEFINE([USE_UNLOCKED_IO], 1,
+    [Define to 1 if you want getc etc. to use unlocked I/O if available.
+     Unlocked I/O can improve performance in unithreaded apps,
+     but it is not safe for multithreaded apps.])
+
   dnl Persuade glibc and Solaris <stdio.h> to declare
   dnl fgets_unlocked(), fputs_unlocked() etc.
   AC_REQUIRE([gl_USE_SYSTEM_EXTENSIONS])