[9fans] waiting for dead procs with libthread

[9fans] waiting for dead procs with libthread

[Fco. J. Ballesteros]

Just wondering. Why is it that proccreate/rfork use RFNOWAIT?
The result is that you can't use threadwaitchan() to learn of
procs created (for things other than exec) that died.

thanks

Re: [9fans] waiting for dead procs with libthread

[Russ Cox]

> Just wondering. Why is it that proccreate/rfork use RFNOWAIT?
> The result is that you can't use threadwaitchan() to learn of
> procs created (for things other than exec) that died.

Just have them send you a message on a channel before
they exit.  Threadwaitchan() exists only because exec'ed
programs can't do that for themselves.

Russ

Re: [9fans] waiting for dead procs with libthread

[Russ Cox]

> Your own procs can't do that either if they die. Right?
> Or perhaps the argument was that in that case it doesn't matter?

If one proc dies unexpectedly, your program is now in an
inconsistent state (maybe it was holding some locks;
maybe it was in the middle of editing some data
structure; etc.) and you are screwed anyway.

Russ

Re: [9fans] waiting for dead procs with libthread

[Fco. J. Ballesteros]

Your own procs can't do that either if they die. Right?
Or perhaps the argument was that in that case it doesn't matter?