They aren't signals in that sense of the word. In the sense of cond_signal().

Basically, the thread in waiting on cond_wait() will not be allocated any timeslices by the scheduler until the other thread calls cond_signal() (or broadcast). So, no polling a second shared var to see if the first is ready yet.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
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In reply to Re^8: need a thread to wait until a buffer is full. by BrowserUk
in thread need a thread to wait until a buffer is full. by exodist

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