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Date: Wed, 25 Apr 2012 07:04:37 -0400
From: Eliot Moss <moss AT cs DOT umass DOT edu>
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To: cygwin AT cygwin DOT com
Subject: Re: xargs: Why does order of command line switches matter?
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On 4/25/2012 6:29 AM, Ronald Fischer wrote:
> Why do I get a different output in the following two invocations of
> xargs? I had expected that the relative order of the command line
> switches (-I, -L) would not matter:
>
> $ ls | xargs -I DIR -L 1 echo DIR
> DIR wontprint.txt
> DIR x.cmd
> DIR x.pl
> DIR x.sh
> $ ls | xargs -L 1 -I DIR echo DIR
> wontprint.txt
> x.cmd
> x.pl
> x.sh
>
>
> xargs (GNU findutils) 4.5.9
> Packaged by Cygwin (4.5.9-2)

I agree that that is what happens, and that it does seem
strange and buggy.  I note, though, that -I *implies* -L 1,
so the -L 1 is unnecessary. Perhaps the explicit mention of
-L 1 "kills" the -I flag in xarg's command line processing.
My guess is that this behavior is passed on from the upstream
implementation and is not specific to cygwin, which means that
the appeal for a change would probably need to be lodged
elsewhere ...

Eliot Moss

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