Passing the output of the last command to sed as an argument

Posted by neurolysis on Super User See other posts from Super User or by neurolysis
Published on 2010-12-21T11:52:09Z Indexed on 2010/12/21 11:56 UTC
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bash

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sed

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xargs

Hi,

Basically, I'm wanting to automate adding something to xorg.conf in the right place, I've used some commands to get the line number of the line I want to manipulate, but I'm not really sure how to go about passing this line number (as an argument and NOT something to be manipulated) to sed. I have been told about xargs and looked at the docs on it, but after some reading and experimentation I can't seem to get it to work.

In case anyone can think of a better method entirely, the process I want to automate is just finding the line containing both "Identifier" and "Monitor0" (there will only be one) and adding a line below it. The problem with just finding Monitor0 and manipulating that line is that there are multiple lines with Monitor0 in.

I've got this far:

fgrep -n "Monitor0" </etc/X11/xorg.conf | fgrep "Identifier" | cut -f1 -d:

This gives out the line number which I'm wanting to pass to sed, but I'm not really sure how to do it.

...or is there a simpler way which I'm not seeing?

Thanks. :)

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