Subj : Re: get num waiters on cv
To   : comp.programming.threads
From : David Schwartz
Date : Mon May 02 2005 01:27 pm


"Maciej Sobczak" <no.spam@no.spam.com> wrote in message 
news:d55d9u$dat$1@sunnews.cern.ch...

>> Is there a way (like say a pthread syscall) to get the number of threads 
>> waiting on a cv and mutex?

> Let's say that there is and you called it and the result was 5.
> What does this number mean *after* the syscall returns?

    If you call it from the only thread that signals the condition variable 
and you don't use timed waits, then you know that at least that many threads 
are waiting. For example, it might make sense to have the thread do the work 
itself if the value is zero rather than signalling the condition variable 
and then doing something else.

    DS

.