There's no persistant lock. cond_wait releases the lock, allowing other threads to cond_broadcast. cond_wait re-obtains the lock on awakening.

You should reread my node. I added this critical paragraph:

The problem might be that your system's implementation of cond_wait isn't atomic (while it should be), allowing a signal to come in after cond_wait unlocks $baton, but before cond_wait starts waiting.

In reply to Re^9: baton passing threads and cond_signal by ikegami
in thread baton passing threads and cond_signal by Anonymous Monk

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