Re: [BUG] Bash not reacting to Ctrl-C

[Chet Ramey]

On 3/7/11 11:52 AM, Linus Torvalds wrote:
> On Mon, Mar 7, 2011 at 8:24 AM, Linus Torvalds
> <torvalds@linux-foundation.org> wrote:
>>
>> and I think one reason why the race is hard to get rid of is simply
>> that system call return is _the_ common point of signal handling in
>> UNIX (technically, obviously any return to user space, but there are
>> no appreciable interrupts etc going on, and there _are_ a lot of
>> system calls). The above trace is one that my patch would have handled
>> correctly (it has no EINTR).
> 
> Linux also ends up making this race easier to see probably because all
> system calls that are interruptible by signals are all "greedy": they
> try to do as much real work as possible, rather than return EINTR.

Yes, the BSDs have traditionally behaved this way as well.  I just had
a much harder time reproducing this on FreeBSD-derived Mac OS X.

Chet

-- 
``The lyf so short, the craft so long to lerne.'' - Chaucer
                 ``Ars longa, vita brevis'' - Hippocrates
Chet Ramey, ITS, CWRU    chet@case.edu    http://cnswww.cns.cwru.edu/~chet/