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Date: Mon, 16 Aug 2010 11:53:52 +0000
From: David Xu <davidxu@freebsd.org>
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To: Kostik Belousov <kostikbel@gmail.com>
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Cc: freebsd-threads@freebsd.org
Subject: Re: PTHREAD_CANCEL_DEFERRED
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Kostik Belousov wrote:

> Missed this, thank you for pointing it out. Updated patch is at
> http://people.freebsd.org/~kib//misc/cancel_defer.2.patch

I found SIGCANCEL is masked by
thr_cancel_deferred(THR_CANCEL_DEFERRED_ENABLE), issignal() does not
return the masked signal, so how a cancellation point syscall can be
interrupted by SIGCANCEL ? I think if a thread being canceled calls
msleep(PCATCH), it should find the signal and return EINTR.