It's a simple crontab wrapper to avoid discarding your crontab file by mistake

crontab

#!/usr/bin/env bash
set -euo pipefail

crontab_bin=/usr/bin/crontab
if (( ${#@} != 1 )); then
  echo 1>&2 "${0##*/} <param>"
  exit 1
fi

if [[ $1 == '-r' ]]; then
  $crontab_bin -e
else
  $crontab_bin $*
fi