Grep Guru

[Bill Campbell]

On Mon, Jun 09, 2008, Raphael Becker wrote:
>On Sun, Jun 08, 2008 at 10:15:50PM +0200, Wojciech Puchar wrote:
>> find . -type f -print0|xargs -0 grep <grepoptions> <text to search>
>
>There's no more need for find | xargs
>
>Try: 
>
>find . -type -f -exec grep <grepoptions> <text to search> {} \+
>
>-exec foo {} \+ behaves like xargs foo  
>-exec foo {} \; exec foo for every file

The issue here is that grep execs grep for each file found while
xargs batches the files.

This is of particular importance if one wants to see the file
names in the output.  In relation to this, if one wants to be
sure that grep always generates the file name, insure that it
always gets at least two files as arguments:

find . -type f -print0 | xargs -0 grep pattern /dev/null

FWIW, I have learned about gnu-grep's -r option reading this
thread, which I had not noticed previously.  I guess that just
goes to show that old habits die hard :-).

Bill
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