Don't try to run SIGCHLD test on win32

greentest/test__monkey_sigchld.py

@@ -19,18 +19,21 @@ def handle_sigchld(*args):
     raise TypeError("This should be ignored but printed")
 
 import signal
-assert signal.getsignal(signal.SIGCHLD) == signal.SIG_DFL
-signal.signal(signal.SIGCHLD, handle_sigchld)
-handler = signal.getsignal(signal.SIGCHLD)
-assert signal.getsignal(signal.SIGCHLD) is handle_sigchld, handler
+if hasattr(signal, 'SIGCHLD'):
+    assert signal.getsignal(signal.SIGCHLD) == signal.SIG_DFL
+    signal.signal(signal.SIGCHLD, handle_sigchld)
+    handler = signal.getsignal(signal.SIGCHLD)
+    assert signal.getsignal(signal.SIGCHLD) is handle_sigchld, handler
 
-pid = os.fork()
-if not pid:
+    pid = os.fork()
+    if not pid:
         # child
         gevent.sleep(0.2)
         sys.exit(0)
-else:
+    else:
         with gevent.Timeout(1):
             while awaiting_child:
                 gevent.sleep(0.01)
             sys.exit(0)
+else:
+    print("No SIGCHLD, not testing")