Port #1220212 (os.kill for Win32) to py3k.
diff --git a/Lib/subprocess.py b/Lib/subprocess.py
index 89cf9bf..ec391cb 100644
--- a/Lib/subprocess.py
+++ b/Lib/subprocess.py
@@ -980,6 +980,10 @@
             """
             if sig == signal.SIGTERM:
                 self.terminate()
+            elif sig == signal.CTRL_C_EVENT:
+                os.kill(self.pid, signal.CTRL_C_EVENT)
+            elif sig == signal.CTRL_BREAK_EVENT:
+                os.kill(self.pid, signal.CTRL_BREAK_EVENT)
             else:
                 raise ValueError("Only SIGTERM is supported on Windows")