On Thu, Jan 10, 2002 at 06:59:54PM +1100, Robert Collins wrote: >> I was going back over this thread before checking in a change to see if >> I'd missed something. >> >> I just realized that I didn't address this concern. Don't know if it >> matters but... >> >> The difference between the SIG_IGN way and the "return TRUE" way is >> that the SIG_IGN way stops the current process from responding to >> a cygwin signal but still lets it respond to a Windows "signal". That >> means that the code in ctrl_c_handle can do its job, if it has to. > >Huh? I actually did the reverse - returning TRUE only prevented >responding to a windows signal, but allowed responding to a cygwin >signal.
Yep. Wrong behavior. The stub should respond to windows signals while the child is initializing. Remember this discussion? >>If we always "return TRUE" in the exec case, then there will be some >>situations where the SIGINT is not delivered to the rest of the process >>group since the code in ctrl_c_handler would be short circuited. > >I don't believe that is the case: Every console process attached to >that console independently recieves the windows signal. Only one has >been disabled. So the execing process's children will still recieve >the windows signals and the cygwin signals. The newly executed subprocess may not have yet set up ctrl_c_handler so it will not do anything but die when CTRL-C comes in. The stub will ignore the CTRL-C. That means that the rest of the processes in the process group will not receive a CTRL-C. >> My SIG_IGN "solution" is wrong, too, though. The SIG_IGN would be >> inherited by the exec'ed process. Then the execed process would never >> see a cygwin SIGINT signal. > >Yes. I still believe that return TRUE is a good solution... but if >you've solved the obvious behaviour I'll be quite now :}. I guess I'm having a hard time understanding why I couldn't just say "race" and have you understand that there is a race but I'll stop now, too. cgf -- Unsubscribe info: http://cygwin.com/ml/#unsubscribe-simple Bug reporting: http://cygwin.com/bugs.html Documentation: http://cygwin.com/docs.html FAQ: http://cygwin.com/faq/
