Merged revisions 84582 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

........
  r84582 | brian.curtin | 2010-09-07 08:24:38 -0500 (Tue, 07 Sep 2010) | 3 lines

  Adjust #8956 to add the bad signal number to the exception message.
........
diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 1691c05..24bf321 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -993,7 +993,7 @@
             elif sig == signal.CTRL_BREAK_EVENT:
                 os.kill(self.pid, signal.CTRL_BREAK_EVENT)
             else:
-                raise ValueError("Unsupported signal")
+                raise ValueError("Unsupported signal: {}".format(sig))
 
         def terminate(self):
             """Terminates the process