Re: Interesting race condition...

David Weinehall
2004-07-26T17:33:30Z

On Sat, Jul 24, 2004 at 01:40:59PM +0000, Marc Ballarin wrote:
> Rob Landley <rob <at> landley.net> writes:
>
> > Oh I can't reproduce it either. (Maybe if I set some kind of loop and left
> > it running for a few days...)
>
> I could reproduce it on an otherwise idle system (2 GHz Athlon, kernel 2.6.7).
> On a loaded system the bug did not occur, which certainly indicates a race
> condition.
>
> Using the following Bash script, the bug appeared 23 times in 122,221
> iterations:
> while [ 1 ];do
> ps ax | grep hack >> TEST
> done
>
> The bug *seems* to be in bash, since an equivalent script in tcsh had no
> problems:
> while ( 1 )
> ps ax | grep hack >> TEST2
> end
>
> This issue has the potential to break a lot of shell scripts in an almost
> undebugable way. Should someone file a bug report via 'bashbug'?

I get this using posh as well, so it doesn't seem to be bash-specific.

Regards: David Weinehall
--
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