Re: Interesting race condition...

From: Marc Ballarin
Date: Sat Jul 24 2004 - 08:51:31 EST


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'?

Marc

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