Hello, I have problem with getProcessOutput, I attempt this code (*) and i change the line : return utils.getProcessOutput("ls",["-l", "-a"]) by : return utils.getProcessOutput("ls",["-l, "."]) it's Ok for this... But when i change by : return utils.getProcessOutput("ls",["-l *"]) or : return utils.getProcessOutput("ls",["-l -a"]) or : return utils.getProcessOutput("ls",["-l ."]) and i have allways this error, but I don't undestand ?? *--- Failure #5 --- --- <exception caught here> --- *--- End of Failure #5 --- Traceback (most recent call last): File "/home/foo/twisted/internet/default.py", line 526, in doSelect ....etc.. "/home/foo/twisted/internet/utils.py", line 44, in errReceived self.deferred.errback(failure.Failure(IOError("got stderr"))) exceptions.AttributeError: 'NoneType' object has no attribute 'errback' *--- Failure #9 --- --- <exception caught here> --- *--- End of Failure #9 --- Traceback (most recent call last): File "/home/foo/twisted/internet/default.py", line 526, in doSelect _logrun(selectable, _drdw, selectable, method, dict) ......etc.. File "/home/foo/twisted/internet/utils.py", line 44, in errReceived self.deferred.errback(failure.Failure(IOError("got stderr"))) exceptions.AttributeError: 'NoneType' object has no attribute 'errback' *--- Failure #13 --- --- <exception caught here> --- *--- End of Failure #13 --- Thank you very much for your help. (*)-------------------------------------------------------- from twisted.internet import protocol, reactor, defer, utils from twisted.protocols import basic class FingerProtocol(basic.LineReceiver): def lineReceived(self, user): self.factory.getUser(user ).addCallback(lambda m: (self.transport.write(m+"\r\n\n")) ).addErrback(lambda x : x.printDetailedTraceback()) class FingerFactory(protocol.ServerFactory): protocol = FingerProtocol def getUser(self, user): return utils.getProcessOutput("ls",["-l -a"]) reactor.listenTCP(1079, FingerFactory()) reactor.run() -- Cordialement Philippe