Trouble with semaphore library

Marc CHALAND l4 at
Tue Oct 23 14:37:54 CEST 2007

Alexander Boettcher <boettcher at>:
> There is one tricky situation if the wakeup message for a semaphore is
> received before the block message. This might happen if the thread
> waiting on that semaphore is preemted by the thread releasing the
> semaphore before it can send the message to the semaphore thread (see
> l4semaphore_down()).

I think what happens in my case is the mirror of that tricky situation
: wakeup message is received just after a releasetimed message.

I agree the correction I proposed is awful :).


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