--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,10 @@
+2010-03-19  Bruno Haible  <bruno@clisp.org>
+
+	Tests of module 'pty' in C++ mode.
+	* modules/pty-tests: New file.
+	* tests/test-pty-c++.cc: New file.
+	* m4/pty_h.m4 (gl_PTY_MODULE_INDICATOR): Invoke gl_MODULE_INDICATOR.
+
 2010-03-19  Eric Blake  <eblake@redhat.com>
 
 	logb: fix documentation

--- a/m4/pty_h.m4
+++ b/m4/pty_h.m4
@@ -1,4 +1,4 @@
-# pty_h.m4 serial 4
+# pty_h.m4 serial 5
 dnl Copyright (C) 2009, 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,
@@ -49,6 +49,8 @@
   dnl Use AC_REQUIRE here, so that the default settings are expanded once only.
   AC_REQUIRE([gl_PTY_H_DEFAULTS])
   GNULIB_[]m4_translit([$1],[abcdefghijklmnopqrstuvwxyz./-],[ABCDEFGHIJKLMNOPQRSTUVWXYZ___])=1
+  dnl Define it also as a C macro, for the benefit of the unit tests.
+  gl_MODULE_INDICATOR([$1])
 ])
 
 AC_DEFUN([gl_PTY_H_DEFAULTS],

new file mode 100644
--- /dev/null
+++ b/modules/pty-tests
@@ -0,0 +1,15 @@
+Files:
+tests/test-pty-c++.cc
+tests/signature.h
+
+Depends-on:
+ansi-c++-opt
+
+configure.ac:
+
+Makefile.am:
+if ANSICXX
+TESTS += test-pty-c++
+check_PROGRAMS += test-pty-c++
+test_pty_c___SOURCES = test-pty-c++.cc
+endif

new file mode 100644
--- /dev/null
+++ b/tests/test-pty-c++.cc
@@ -0,0 +1,43 @@
+/* Test of <pty.h> substitute in C++ mode.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2010.  */
+
+#define GNULIB_NAMESPACE gnulib
+#include <config.h>
+
+#include <pty.h>
+
+#include "signature.h"
+
+
+#if GNULIB_FORKPTY
+SIGNATURE_CHECK (GNULIB_NAMESPACE::forkpty, int,
+                 (int *, char *, struct termios const *,
+                  struct winsize const *));
+#endif
+
+#if GNULIB_OPENPTY
+SIGNATURE_CHECK (GNULIB_NAMESPACE::openpty, int,
+                 (int *, int *, char *, struct termios const *,
+                  struct winsize const *));
+#endif
+
+
+int
+main ()
+{
+}