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Date: Tue, 15 Jul 2008 14:02:24 -0500
From: David Kelly <dkelly@hiwaay.net>
To: Gary Kline <kline@thought.org>
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	<20080715183500.GA76088@thought.org>
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Cc: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>,
	FreeBSD Mailing List <freebsd-questions@freebsd.org>
Subject: Re: why is this script failing?
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On Tue, Jul 15, 2008 at 11:35:00AM -0700, Gary Kline wrote:
> On Tue, Jul 15, 2008 at 07:37:02AM +0200, Wojciech Puchar wrote:
> > >
> > >	why is this script not finding them?
> > >
> > >
> > >wav=/tmp/kde-kline/\*wav\*
> > 
> > why you put \ before *
> 
> 	to allow the shell to catch various formsof strings with "wav"
> 	embedded.

I questioned that escape earlier.

Without the \ escape the variable ${wav} will contain all the files
matching the pattern. But with the escape it will literally be 
"/tmp/kde-kline/*wav*". Wildcard expansion doesn't occur until later
when Gary does something like this:

rm ${wav}

which is processed as if he had just now typed:

rm /tmp/kde-kline/*wav*

while without the escape it might appear like this:

rm /tmp/kde-kline/file1.wav /tmp/kde-kline/file2.wav

Is probably best to postpone wildcard expansion until the last moment
because if any of the filenames contain spaces the space will probably
cause a break between arguments. The first time the wildcard expands to
a filename with a space the space will be escaped. But the second time
you use it that escape is lost. So its best to expand it in the place
its needed.

-- 
David Kelly N4HHE, dkelly@HiWAAY.net
========================================================================
Whom computers would destroy, they must first drive mad.