Subj : Re: Question : usage of conditional variables.
To   : comp.programming.threads
From : Jamie
Date : Thu Jun 09 2005 03:39 am

Thanks David!

Yeh, I had wrong understanding with condition variables, still
complicated.
Aftter I put the predicate (ready : TRUE/FALSE), my program runs well.

But, what is this predicate for? A site said that "pthread_cond_wait()
is recommended to be used in a loop testing the predicate associated
with it. This will take care of any spurious wakeups that may occur."

My program runs well for a while without predicate(not using a loop),
but it stops and wait a signal forever at some point.. After adding a
predicate and checking it before calling pthread_cond_wait(), it runs
well. But I can't understand why sometimes it works well without
predicate and sometimes not.. What does the spurious wakeups really
mean? 


I'm still confused about it..

.