Subj : Re: Question : usage of conditional variables.
To   : comp.programming.threads
From : David Schwartz
Date : Wed Jun 08 2005 10:26 pm


"Jamie" <TechJimin@gmail.com> wrote in message 
news:1118276552.328458.251780@g47g2000cwa.googlegroups.com...
> Program Summary:
>  1) Making two threads (tA, tB)
>  2) tA send a conditional signal to tB
>  3) tB recv a conditional signal
>  4) tB send a conditional signal to tA
>  5) tA recv a conditional signal
>  6) repeat through 2 to 5.

    You are thinking about this all wrong. You use pthread_cond_wait to wait 
for a condition if that condition is not yet ready. You have no condition to 
wait for. So your code will not do anything sensible. You always wait like 
this:

pthread_mutex_lock(...)
while(condition_not_right) pthread_cond_wait(...)
do_stuff();
pthread_mutex_unlock(...)

    DS

.