Declare system functions in a way that works with C++.

[gnulib.git] / m4 / ioctl.m4

diff --git a/m4/ioctl.m4 b/m4/ioctl.m4
index e799600..a1db8fc 100644 (file)
--- a/m4/ioctl.m4
+++ b/m4/ioctl.m4
@@ -1,4 +1,4 @@
-# ioctl.m4 serial 3
+# ioctl.m4 serial 4
 dnl Copyright (C) 2008-2011 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
@@ -24,7 +24,12 @@ AC_DEFUN([gl_FUNC_IOCTL],
       [AC_COMPILE_IFELSE(
          [AC_LANG_PROGRAM(
             [[#include <sys/ioctl.h>]],
-            [[extern int ioctl (int, int, ...);]])
+            [[extern
+              #ifdef __cplusplus
+              "C"
+              #endif
+              int ioctl (int, int, ...);
+            ]])
          ],
          [gl_cv_func_ioctl_posix_signature=yes],
          [gl_cv_func_ioctl_posix_signature=no])