Sunday, October 7. 2007
xargs
If not already in your toolbox, xargs should be:
read items from the standard input, delimited by blanks (which can be protected with double or single quotes or a backslash) or newlines, and executes the command (default is /bin/echo) one or more times with any initial- arguments followed by items read from standard input. Blank lines on the standard input are ignored.
Perfect to remove the need for a for loop in this example like so:
ps -ef | grep nobody | awk '{print $2}' | xargs kill -9
pkill -9 nobody
an appropriate xargs example would be:
find . | xargs grep test123
There’s always another and frequently shorter way… I was just illustrating the concept for the related blog post with a for loop in place of xargs. 
For your example you could do this on linux:
grep -R test123 .
Also, on Linux (or any system that uses the GNU find and GNU xargs), you can use
find . -type f -print0 | xargs -0 do_something_useful
The -print0 causes the files to be printed separated by null characters instead of new lines, -0 expects the incoming data to be separated by null characters. This is good for places where you might have file names with embedded spaces, since otherwise xargs won’t pass the filename on to do_something_useful correctly.
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