Subj : Re: thread control by mutex, predicates and conditions puzzle
To   : comp.programming.threads
From : Jomu
Date : Fri Jan 07 2005 10:15 am

There are signals which will get you out of pthread_cond_wait, probably
all (I can't recall any exceptions). Your thread waiting on condition
will get EINTR as result of pthread_cond_wait and there you can handle
situtation. Of course, signal itself is supposed to be handled in it's
handler and after getting EINTR it is up to your thread to lookup state
changed by that handler.

As for your solution, I think I am a bit too practical to see through
all this generalization :). Other elements are looking fine, except
this notify_all - you have to pthread_cond_broadcast them all (or
rewrite pthread_cond_wait so it marks used conditions at moment -
ouch). To register them, you have to use protected list or something
similar, and to notify them, you have to lock it, iterate rhtough and
broadcast every one. Very intensive variable update operation, IMO :).

What is this stop/start action thing? Do you want to freeze your
threads only at some points or wherever they happen to be when you stop
them?

dd

.