George Russell wrote:
Dean Herington wrote:
George Russell wrote:
Posix.runProcess really should use it I think.
No, it's better to be able to choose the way to handle this. Maybe add a flag to Posix.runProcess. But the whole GHC.Conc.forkProcess isn't finished, yet, anyway. I don't really see the point of allowing the user to choose the old way. Posix.runProcess is supposed to fork off a new process outside of this runtime system. I don't see any way this can be helped by allowing other
Volker Stolz wrote: threads to continue in the child until the actual time of exec, unless for some reason the evaluation of the arguments to exec somehow relies on other threads. But this would surely at least require argument evaluation to unsafely conceal IO, and in any case could be better fixed by forcing the arguments to be fully evaluated before the fork.
Let's not forget that the new (child) process may never do exec(). I have an interpreter that forks to replicate itself, relying on the runtime system to carry over.
Er, are you confusing Posix.forkProcess (which I was talking about) with Posix.runProcess (which is what I am talking about now)?
Sorry for confusing them. I agree with you that, for Posix.runProcess, auxiliary threads should not be allowed to continue in the child process. In fact, I had to abandon use of Posix.runProcess in my application because it (currently) allows those threads to continue. A second reason Posix.runProcess didn't do the job for me is that it doesn't return a handle to the child process, as you also pointed out. Concerning forking a process (without necessarily doing exec), I agree with Volker that an option to control retention or deletion of auxiliary threads is desirable. Dean