Re: [Valgrind-users] New experimental skin: signal handler checker

[Dan K. <da...@ke...>]

Dan Kegel wrote:
> Jeremy Fitzhardinge wrote:
> 
>>> Even in more complicated situations, a circular buffer between the
>>> signal handler as producer and the mainline code as consumer,
>>> would violate the rule about "no touching" the control pointers
>>> of the circular buffer.
> 
> Yep.  In other words, there's something iffy about the
> whole idea of signal handlers

Arrgh.  Clicked 'send' by mistake.  I meant to say "classic signal handlers".
The current Unix standard,
http://www.opengroup.org/onlinepubs/007904975/functions/sigaction.html
has this to say about the issue:

"In order to prevent errors arising from interrupting non-reentrant
function calls, applications should protect calls to these functions
either by blocking the appropriate signals or through the use of
some programmatic semaphore (see semget() , sem_init() , sem_open(),
and so on). ..."

- Dan

-- 
Dan Kegel
http://www.kegel.com
http://counter.li.org/cgi-bin/runscript/display-person.cgi?user=78045