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Date: Fri, 17 Sep 2004 17:36:17 +1000 (EST)
From: luke DOT kendall AT cisra DOT canon DOT com DOT au
Subject: Re: Bash returns incorrect process status
To: cygwin AT cygwin DOT com
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Message-Id: <20040917073617.AE94C84C4D@pessard.research.canon.com.au>

On 16 Sep, Pierre A. Humblet wrote:
>  But bash seems to keep at least CHILD_MAX jobs, each one of them possibly 
>  with many (unbounded) processes. It is very easy to produce situations 
>  where bash keeps track of thousands of pids. Many of those pids (e.g. the 
>  first ones in pipelines) will have been waited on, and nothing prevents the 
>  OS from reusing them. Pid aliasing can easily occur even if the OS never 
>  reuses a pid in CHILD_MAX consecutive forks from a process. 

I'm coming in to this discussion late, and this is probably way off
topic.  But I once thought bash wasn't reporting status of the previous
command properly (as reported via $?), when what was really happening
was that I was executing other commands as part of my bash prompt, and
bash was reporting the (successful) status of the last of those
commands!

I.e. I'd get a different result by doing:

    some-command
    if [ $? = 0 ]
    then ...

and doing

    some-command && ...

luke


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