> A separate program would clobber it. Nope, you can check the return value from the program(s) run inside of it and revert to the backup file if there's a pro

> A separate program would clobber it. Nope, you can check the return value from the program(s) run inside of it and revert to the backup file if there's a problem. You really don't need it to be handled specifically by sed. There's actually an example script that does exactly that in _The Unix Programming Environment_, called 'overwrite', on page 154.