Does pthread_cond_signal function unlock the mutex the calling thread locked?

Question

When i call 'pthread_cond_signal' during my thread's function, does this call unlock the mutex i currently use? (Not the one the pthread_cond_wait is waiting for).

score 5 · Accepted Answer · answered Apr 05 '11 at 13:30

5

Only the mutex given to pthread_cond_(timed_)wait() is unlocked to give other threads the chance to change the condition. At the end of pthread_cond_wait, the mutex is locked again. No other functions lock/unlock mutexes.

answered Apr 05 '11 at 13:30

stefaanv

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score 3 · Answer 2 · answered Apr 05 '11 at 13:30

3

No, it doesn't unlock any mutex at all. pthread_cond_wait does unlock its mutex, and when it exits the mutex is locked again.

answered Apr 05 '11 at 13:30

Mark B

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I'm pretty sure from my reading that both answers are saying about the same thing just in slightly different ways. – Mark B Dec 03 '19 at 19:47

Does pthread_cond_signal function unlock the mutex the calling thread locked?

2 Answers2