diff -r f2d955afad8a Lib/test/test_signal.py
--- a/Lib/test/test_signal.py	Sat Aug 17 21:43:47 2013 +0200
+++ b/Lib/test/test_signal.py	Sun Aug 18 08:15:49 2013 +0800
@@ -305,7 +305,8 @@
         except ZeroDivisionError:
             # An ignored exception should have been printed out on stderr
             err = err.getvalue()
-            if ('Exception ignored when trying to write to the signal wakeup fd'
+            if ('Exception ignored when trying to write to the signal '
+                'wakeup fd: %d' % errno.EBADF
                 not in err):
                 raise AssertionError(err)
             if ('OSError: [Errno %d]' % errno.EBADF) not in err:
diff -r f2d955afad8a Modules/signalmodule.c
--- a/Modules/signalmodule.c	Sat Aug 17 21:43:47 2013 +0200
+++ b/Modules/signalmodule.c	Sun Aug 18 08:15:49 2013 +0800
@@ -182,7 +182,7 @@
     errno = (int) (Py_intptr_t) data;
     PyErr_SetFromErrno(PyExc_OSError);
     PySys_WriteStderr("Exception ignored when trying to write to the "
-                      "signal wakeup fd:\n");
+                      "signal wakeup fd: %d\n", errno);
     PyErr_WriteUnraisable(NULL);
     errno = save_errno;
     return 0;