Tip #1: Renaming Multiple Files in Bash

Sometimes you want to rename a set of files, applying some sort of common replacement to each filename. For example, suppose we have a set of files with the extension jpeg that we wish to rename to the more concise jpg. Our set of files is shown below:

linux@devbox:~/tip1> ls -la
total 1
drwxr-xr-x 2 linux users 168 2008-05-05 01:24 .
drwxr-xr-x 9 linux users 640 2008-05-05 01:24 ..
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l1.jpeg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l2.jpeg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l3.jpeg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l4.jpeg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l5.jpeg

All you need is one simple line:

linux@devbox:~/tip1> for file in `ls *.jpeg`; do mv $file ${file/jpeg/jpg}; done

Voilà!

linux@devbox:~/tip1> ls -la
total 1
drwxr-xr-x 2 linux users 168 2008-05-05 01:52 .
drwxr-xr-x 9 linux users 640 2008-05-05 01:24 ..
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l1.jpg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l2.jpg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l3.jpg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l4.jpg
-rw-r--r-- 1 linux users 0 2008-05-05 01:24 l5.jpg