mask in waitQSem

Brandon Allbery allbery.b at
Fri Nov 14 21:30:11 UTC 2014

On Fri, Nov 14, 2014 at 4:23 PM, Yuras Shumovich <shumovichy at>

> Here mask is used, but I looks completely useless for me. waitQSem
> itself should be called with async exceptions masked, otherwise there is
> no way to prevent resource leak.
> Do anyone know why mask is used here?

I thought QSem was known to be completely unsafe and was recommended instead,
with QSem and friends slated for removal?

In any case, there are probably leftover attempts to make it safe, yes.

brandon s allbery kf8nh                               sine nomine associates
allbery.b at                                  ballbery at
unix, openafs, kerberos, infrastructure, xmonad
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