Hi all,
I've been hunting on google for this with no luck. It seems to crop up a lot for me so I thought there might be someone out there who could help me.

I often want to rename all files containing some string to something else, for example I might want to rename

application_testing.cpp
application_testing.sht
application_testing.shm
application_testing.mnt

to:

google_testing.cpp
google_testing.sht
google_testing.shm
google_testing.mnt

how can I do it? I thought it'd be something along the lines of:

find . -name application_testing* -exec mv {} google_testing*;

but that doesn't work. any thoughts?

This will work for files in the same directory.

for file in `find ./ -name "application_testing*"`; do file=${file#./*}; mv -v ${file} google${file#application}; done

You could also do:
for file in application_testing.*; do mv -v ${file} google${file#application}; done

If you want to rename files also in subdirectories, you need to decompose the directory and basename parts and change just the basename:
for file in `find ./ -name "application_testing*"`; do targetdir=`dirname $file`; bname=`basename $file`; mv $file ${targetdir}/google${bname#application}; done

Remember, that if its possible that the filenames contain whitespace or special shell characters, you need to put the variables inside double quotes: "${file}" or "${file#application}"

With the find command, if the pattern you are searching for uses wildcards, you need to add double quotes around the pattern, so that the shell doesn't expand the wild cards first.

Your original
find . -name application_testing*
would expand to: find. -name application_testing.cpp application_testing.mnt application_testing.mnt application_testing.sht

works a treat, thanks!

I've written a small script to do it now (and added some other useful stuff )

I have one other question though, I have to run the script a few times to make sure that it's renamed all the subdirectories and their subfiles - the reason being that it renames the top level directory first and then can't find the subdirectories any longer as the path has changed. Is there any way I can force it to begin renaming from the deepest level first?

First, of all, you could select just files by using the -type f option to the file command. Your description was about changing the names of files.

You could try the -mindepth options:
- Option: -mindepth levels
Do not apply any tests or actions at levels less than LEVELS (a
non-negative integer). `-mindepth 1' means process all files
except the command line arguments.

Also look at the -depth option.
The find man page would make a good read because it is such a powerful utility.

If you 'man' command has the option try
man -Tdvi find >find.dvi
or
man -Tps find >find.ps
to produce a dvi or post script file that is suitable for printing.