Everyday something new to learn with Unix

Anyway, Sean Kelly was doing some commandline magic in his webcast comparing J2EE with things like Zope and RoR and used something I had never seen before:

You want to rename a folder for example correcting a plural form or something similiar:

mv picture{,s}

This will rename the folder/file "picture" into "pictures". Very handy :D Actually it will simply take the word "picture" and split it up into 2 strings: One without and one with "s" appended. Just try it with something like this:

echo {hello,world}

Absolutely cool, also for creating multiple folders within a shared parent directory ;-)

mkdir /Users/zerok/{hello,world}

After some short checking the Bash reference manual I now know, that this feature is called "brace expansion".