I was wondering if it was possible to run a custom script on save based on certain file names in textmate. For example I'd like to auto compile a C program sometime on save.
As far as I know, there's no way to do this as you described, for all save situations (i.e., using Command-S, selecting File->Save, etc.).
You might be able to create a custom bundle item that saves the document and executes your script, and assign it Command-S, so that it runs when you use that keyboard shortcut.
It's actually fairly easy to do this using a custom command in a bundle.
Here's how to make a simple command:
That's it. You should now have a command which saves the file, and runs a command.
You can probably do something with TextMate commands by using a macro in a similar way.