[Boost-users] [signals] callback for synchronization, how to do?

Hi all, maybe a simple question, but I just can't figure it out: I have a class which triggers an action on a remote device. A different thread polls for the response and sends a signal that the response has arrived. What I simply want is a blocking call like this: // connect to the signal which reports the response otherClass.sigResponse().connect( some sort of lamda magic?) SendCommand(cmd); // Wait somehow until the response has arrived WaitForSigResponse(); return; Any help appreciated. Thanks, Rainer