Re: [PATCH 4/4] [MAIN] Optimize dash -c "command" to avoid a fork

[Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxxx>]

On Sun, Apr 10, 2011 at 07:36:49AM +0000, Jonathan Nieder wrote:
> From: Jilles Tjoelker <jilles@xxxxxxxx>
> Date: Sat, 13 Jun 2009 16:17:45 -0500
> 
> This change only affects strings passed to -c, when the -s option is
> not used.
> 
> Use the EV_EXIT flag to inform the eval machinery that the string
> being passed is the entirety of input.  This way, a fork may be
> omitted in many special cases.
> 
> If there are empty lines after the last command, the evalcmd will not
> see the end early enough and forks will not be omitted. The same thing
> seems to happen in bash.
> 
> Example:
>   sh -c 'ps lT'
> No longer shows a shell process waiting for ps to finish.
> 
> [jn: ported from FreeBSD SVN r194128.  Bugs are mine.]
> 
> Signed-off-by: Jonathan Nieder <jrnieder@xxxxxxxxx>

OK I will take this patch since its impact is much smaller than
one that hacks around the input path, and seems to achieve most of
what you want anyway.

I will roll it and the EV_EXIT exporting patch into one.

Thanks,
-- 
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
Home Page: http://gondor.apana.org.au/~herbert/
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