Subject: Re: sh reads byte by byte
To: Manuel Bouyer <>
From: Greg A. Woods <>
List: tech-userlevel
Date: 02/21/2007 18:24:57
At Sat, 20 Jan 2007 17:01:08 +0100,
Manuel Bouyer wrote:
> while trying to see how to speedup audit-packages as used by the bulk builds,
> I noticed (using ktrace) that something like this:
> #!/bin/sh
> while read a b c; do
> echo $a $b $c
> done < /tmp/file
> will read /tmp/file byte by byte. With the current pkg-vulnerabilities
> this makes 221909 syscalls. Would there be a way to have it read the
> file in a more efficient way (rewriting it in another language is not an
> option for now) ?

Why not rewrite?  That would seem to be the correct solution.  Can't
AWK, for example, do the job?

If you're talking specifically about the "while read pat type url; do"
loop in audit-packages, then that would indeed seem to be an ideal
application for AWK.

						Greg A. Woods

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