Patch File Updater
Sometimes you will want to update your patches from one version to another, so that the goal is to go from having one patch file against an old version of the file, to a new patch file against a new version of the file. This script handles that for you transparently. All you have to do is call:
./update_script file.old file.old_patch file.current
And you will get a file called file.old_patch.updated as your new patch file. And that is all that there is to it.