ttyname_r: Make it work on MacOS X 10.4 and Solaris 10.

[gnulib.git] / m4 / ttyname_r.m4

diff --git a/m4/ttyname_r.m4 b/m4/ttyname_r.m4
index 54a8676..ce47374 100644 (file)
--- a/m4/ttyname_r.m4
+++ b/m4/ttyname_r.m4
@@ -1,4 +1,4 @@
-# ttyname_r.m4 serial 1
+# ttyname_r.m4 serial 2
 dnl Copyright (C) 2010 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -11,6 +11,24 @@ AC_DEFUN([gl_FUNC_TTYNAME_R],
   AC_CHECK_FUNCS([ttyname_r])
   if test $ac_cv_func_ttyname_r = no; then
     HAVE_TTYNAME_R=0
+  else
+    dnl On MacOS X 10.4 and Solaris 10 the return type is 'char *', not 'int'.
+    AC_CACHE_CHECK([whether ttyname_r is compatible with its POSIX signature],
+      [gl_cv_func_ttyname_r_posix],
+      [AC_COMPILE_IFELSE(
+         [AC_LANG_PROGRAM(
+            [[#include <stddef.h>
+              #include <unistd.h>]],
+            [[*ttyname_r (0, NULL, 0);]])
+         ],
+         [gl_cv_func_ttyname_r_posix=no],
+         [gl_cv_func_ttyname_r_posix=yes])
+      ])
+    if test $gl_cv_func_ttyname_r_posix = no; then
+      REPLACE_TTYNAME_R=1
+    fi
+  fi
+  if test $HAVE_TTYNAME_R = 0 || test $REPLACE_TTYNAME_R = 1; then
     AC_LIBOBJ([ttyname_r])
     gl_PREREQ_TTYNAME_R
   fi