diff -r 4c0d38670f41 Lib/test/test_signal.py
--- a/Lib/test/test_signal.py	Tue Oct 16 22:50:34 2012 +0300
+++ b/Lib/test/test_signal.py	Tue Oct 16 17:19:20 2012 -0300
@@ -265,6 +265,42 @@
 
         assert_python_ok('-c', code)
 
+    def test_wakeup_read_only_fd(self):
+        # use a subprocess to have only one thread
+        code = """if 1:
+        try:
+            import fcntl
+            import sys
+            import os
+            import signal
+            import time
+
+            def handler(signum, frame):
+                pass
+
+            signal.signal(signal.SIGALRM, handler)
+            read, write = os.pipe()
+            for fd in (read, write):
+                flags = fcntl.fcntl(fd, fcntl.F_GETFL, 0)
+                flags = flags | os.O_NONBLOCK
+                fcntl.fcntl(fd, fcntl.F_SETFL, flags)
+
+            # set wakeup_fd a read file descriptor to trigger the error
+            signal.set_wakeup_fd(read)
+
+            signal.alarm(1)
+            while range(10):
+                time.sleep(0.2)
+
+            os.close(read)
+            os.close(write)
+            sys.exit(-1)
+        except OSError:
+            sys.exit(0)
+        """
+
+        assert_python_ok('-c', code)
+
     def test_wakeup_fd_early(self):
         self.check_wakeup("""def test():
             import select
diff -r 4c0d38670f41 Modules/signalmodule.c
--- a/Modules/signalmodule.c	Tue Oct 16 22:50:34 2012 +0300
+++ b/Modules/signalmodule.c	Tue Oct 16 17:19:20 2012 -0300
@@ -172,15 +172,30 @@
     return PyErr_CheckSignals();
 }
 
+static int
+checksignals_errno(void * unused)
+{
+    int error = (int) unused;
+    if (error) {
+        return PyErr_SetFromErrno(PyExc_OSError);
+    }
+    return PyErr_CheckSignals();
+}
+
 static void
 trip_signal(int sig_num)
 {
     unsigned char byte;
+    int rc = 0;
 
     Handlers[sig_num].tripped = 1;
     if (wakeup_fd != -1) {
         byte = (unsigned char)sig_num;
-        write(wakeup_fd, &byte, 1);
+        while ((rc = write(wakeup_fd, &byte, 1)) == -1 && errno == EINTR);
+        if (rc == -1) {
+            Py_AddPendingCall(checksignals_errno, errno);
+            return;
+        }
     }
     if (is_tripped)
         return;