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Date: Fri, 10 Oct 2008 06:21:06 -0600
From: Eric Blake <ebb9 AT byu DOT net>
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To: cygwin AT cygwin DOT com, effbiae AT gmail DOT com
Subject: Re: optimizing fork/exec in vendor source
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According to Jack Andrews on 10/9/2008 11:25 PM:
> in the example, i guess all that is done is to fork and exec ls,
> grabbing its stdout.  this can be done with CreateProcess() easily
> without having to emulate everything that fork does.  so my real
> question is, has anyone tried optimizing fork/exec to CreateProcess()?

No, changing bash to use CreateProcess is not the answer.  The real
question is whether someone with copyright assignment is willing to write
posix_spawn[p], and write it more efficiently than forking, at which
point, bash should be patched to take advantage of it, at least when
exec'ing subprocesses (it won't help the other common case where bash
truly must fork, such as in creating subshells, but might speed up the
execution of child processes).

>  and would the maintainers of (eg. bash) accept a patch for use with
> cygwin?  (so i wouldn't have to continually forward port my fork/exec
> code).

You are welcome to post whatever patch you'd like.  But in the case of
bash, if the patch uses native Windows calls, I'm very unlikely to either
apply it or to pass it upstream, as it would just be a maintenance
nightmare, not to mention too risky of breaking posix semantics by going
behind cygwin's back.

- --
Don't work too hard, make some time for fun as well!

Eric Blake             ebb9 AT byu DOT net
volunteer cygwin bash maintainer
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