In Linux, how do I run a shell script when a file or directory changes

Question

I want to run a shell script when a specific file or directory changes.

How can I easily do that?

Answer 1

Check out the kernel filesystem monitor daemon

http://freshmeat.net/projects/kfsmd/

Here's a how-to:

http://www.linux.com/archive/feature/124903

Answer 2

Use inotify-tools.

Answer 3

As mentioned, inotify-tools is probably the best idea. However, if you're programming for fun, you can try and earn hacker XPs by judicious application of tail -f .

Answer 4

Here's another option: http://fileschanged.sourceforge.net/

See especially "example 4", which "monitors a directory and archives any new or changed files".