Date: Tue, 15 Jul 2008 14:02:24 -0500 From: David Kelly <dkelly@hiwaay.net> To: Gary Kline <kline@thought.org> Cc: Wojciech Puchar <wojtek@wojtek.tensor.gdynia.pl>, FreeBSD Mailing List <freebsd-questions@freebsd.org> Subject: Re: why is this script failing? Message-ID: <20080715190224.GC21840@Grumpy.DynDNS.org> In-Reply-To: <20080715183500.GA76088@thought.org> References: <20080714201241.GA22443@thought.org> <20080715073651.P1638@wojtek.tensor.gdynia.pl> <20080715183500.GA76088@thought.org>
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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.
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