Yesterday I found that I couldn't deploy because we were out of disk space. I needed to delete some of the old release folders.
When I sshed into the server and looked in the releases folder, it had a ton of folders named like this:
20120126191222 20120126193901 20120127153732 20120127171244 20120127204235 20120127204517 20120130172837 20120131152908 20120131160422Here you see some from 2012, but they went back all the way to 2010. I wanted to delete everything older than 2012.
Enter the magic of xargs. It lets you take the output of one command and input each line of it as an argument to another command.
Here's what I did:
ls # shows me all the folders ls | grep ^201 # shows only the ones starting with 2010 or 2011 ls | grep ^201 | xargs rm -rf # delete all thoseBuilding up the command bit-by-bit lets me verify that I'm going to delete the right things. And xargs knocks it out.
Here's another useful example. Vim creates a temporary .swp files that sometimes don't get cleaned up. To find and delete them all out of a folder:
find . -name '*.swp' | xargs rm