Hello
i have such code in one thread1:

pthread_mutex_lock(m)
if (something)
pthread_cond_signal(c)
pthread_mutex_unlock(m)

and in thread2:
pthread_mutex_lock(m)
if (something2)
pthread_cond_wait(c,m)
pthread_mutex_unlock(m)

Thread2 wait on pthread_cond_wait(), and after that Thread1 calls
pthread_cond_signal(). I am not sure what is next. Does:

in this moment thread1 calls pthread_mutex_unlock(m), and after that
thread2 receives mutex m, and then unlock it and finishes ?
So in such case Thread2 does not start immediately after receiving
signal on conditional value, because it must wait for mutex, am i right ?

Thanx
Michal

[ Post a follow-up to this message ]

> in this moment thread1 calls pthread_mutex_unlock(m), and after that
> thread2 receives mutex m, and then unlock it and finishes ?
> So in such case Thread2 does not start immediately after receiving
> signal on conditional value, because it must wait for mutex, am i right ?

You are right 
The thread has to re-acquire the mutex ownership before it can leave the
pthread_cond_wait routine. (This is also true on cancellation or timer
expiration with pthread_cond_timedwait).

Regards,
Seb.

[ Post a follow-up to this message ]