I have used echo as a sort of poor mans equivalent for a safe check of a pipeline, removing the echo when I felt the rest of the pipeline was working correctly.

I have used echo as a sort of poor mans equivalent for a safe check of a pipeline, removing the echo when I felt the rest of the pipeline was working correctly. shell stuff | xargs -n 1 -I % echo real command and % args I have also been known to write scripts where instead of executing the critical parts it prints them. Then a dry run is script and the real run is script | sh