Re: [LUG] GNU parallel

[Philip Hudson <phil.hudson@xxxxxxxxx>]

On 20 May, 2012, at 3:49 pm, Simon Waters wrote:

> On 20/05/12 14:28, Philip Hudson wrote:
> > Just became aware of this last week, installed it and got a few basic
> > scripts working with it instead of xargs. But I *cannot* work out  
> > how to
> > get it to pipe. I have RTFMed til I'm sick of the sight of the page  
> > and
> > I've googled every which way. Anyone got a clue?
>
> Tell us what you are trying to do, how you try to do it, and what the
> result is.
>
> I just downloaded parallel-20120422, unpacked, configure, make, cd  
> src, and
>
> find . -name "*.html" | ./parallel tidy | less
>
> Does pretty much what I would expect.
>
> http://catb.org/~esr/faqs/smart-questions.html

Trying to filter filenames using grep. To extend your example (which I  
don't believe can have worked correctly as transcribed, BTW, except  
accidentally):

find . -name '*.html' | parallel --WTF-works-here-to-pipe-into grep -- 
only-matching '<regexp>'

Where I want to run grep on each filename itself, not the contents of  
the named file; in other words, I want parallel to pipe each filename  
into grep on stdin, not pass it as a (filename) parameter to an  
invocation of grep.

Your example uses parallel to pass a different parameter to each  
invocation of tidy and only then to pipe anything further. I want  
parallel to pipe a different stream (happening to be a filename) into  
each invocation of grep on stdin.

Hope that's clear, and thanks for answering.

--
Phil Hudson                  http://hudson-it.no-ip.biz
@UWascalWabbit                 PGP/GnuPG ID: 0x887DCA63


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