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Date: Fri, 19 Sep 2008 12:40:28 -0400 (EDT)
From: Daniel Eischen <deischen@freebsd.org>
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To: Stephen Montgomery-Smith <stephen@math.missouri.edu>
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Cc: freebsd-hackers@freebsd.org, FreeBSD Stable <freebsd-stable@freebsd.org>
Subject: Re: Calling malloc from a signal handler
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On Fri, 19 Sep 2008, Stephen Montgomery-Smith wrote:

> I notice that if you use "malloc" from within a signal handler on 
> FreeBSD-6.x, that you can potentially trigger a "recursive call" error.
>
> But this seems to have changed in FreeBSD-7.x.
>
> Is it now permissible to call "malloc" from within a signal handler in 
> FreeBSD-7.x?
>
> If so, should the man page of "sigaction(2)" be upgraded to say this?

You shouldn't call malloc() or any other function that
isn't async-signal-safe from a signal handler.  I don't
think we should say if it works or not, since it is
not portable and could change at any given time in
future versions of FreeBSD.

-- 
DE