Run a function on interrupt or error

It is sometimes necessary for a script to clean up when exiting prematurely. Perhaps some temporary files are written to, and the execution is halted due to an error or a user interrupt (ctrl-c).

We can do so using trap:

cleanup() {
  rm some-temp-file-maybe
  # ... other actions
  exit 1
}

trap cleanup ERR SIGINT

We're tying the cleanup function to the signals ERR and SIGINT. This function will be called if the script exits with a non-zero return code or if it is interrupted using ctrl-c.

Source: man trap