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To: Garrett Cooper <youshi10@u.washington.edu>
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Comments: In-reply-to Garrett Cooper <youshi10@u.washington.edu>
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Date: Thu, 14 Jun 2007 11:08:04 +0300
From: Danny Braniss <danny@cs.huji.ac.il>
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Cc: hackers@freebsd.org
Subject: Re: Using shell commands versus C equivalents 
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...
> Sorry -- actually I meant that (along similar lines), there was a 
> program with the following lines:
> 
> vsystem("/bin/chmod +x %s", filename);
> 
> and I replaced it with:
> 
> chmod(filename, (mode_t) ( S_IXUSR | S_IXGRP | S_IXOTH ));
> 
> Probably won't yield much gain overall, but every drop counts and there 
> are quite a few iterations performed in the pkg_* programs, in 
> particular dealing with X.org.

chmod is one(1) system call, while system is many, for starters it's
fork/exec, which btw, is quiet expensive, haven't counted, but my gut feeling
it's in the 10s.
So, if the program does this chmod once in a blue moon, there is no real
argument, but if id does it many times, then one system call is a real winner,

danny