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From: mark@spider.co.uk (Mark Valentine)
Newsgroups: comp.unix.shell
Subject: Re: How to read sequentially from a file in SH (not KSH)
Message-ID: <1991Apr29.105329.20148@spider.co.uk>
Date: 29 Apr 91 10:53:29 GMT
References: <1991Apr27.012336.2732@shibaya.lonestar.org> <232@bria.UUCP>
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afc> while read VAR1 VAR2 < $FILENAME; do
afc>   echo $VAR1 $VAR2
afc> done
afc>
afc> but I keep reading the first line in the file over and over.  Nothing in
afc> the manual page seems to be usable in this situation.  How is this done
afc> under SH?  Is it possible?

mike> cat $FILENAME | while read VAR1 VAR2
mike> do echo $VAR1 $VAR2
mike> done

Sometimes this doesn't fit into the logic of a shell script.  In such cases
I find that something like following works nicely.

    exec 3< $FILENAME
    while read VAR1 VAR2 <&3
    do echo $VAR1 $VAR2
    done

This is especially handy if you have a couple of files you're reading
simultaneously in the body of the loop, or the conditional isn't based
on the read itself.

		Mark.
-- 
Mark Valentine, Spider Systems <mark@spider.co.uk>            /\oo/\