Simple admin Postfix emails in bash

A simple script for quick Postfix system email management.

#!/bin/bash

RETVAL=0

case $1 in
count)
        mailq | tail -n 1
        ;;
list)
        COUNT=$(mailq | grep -c "^[A-F0-9]")
        if [[ $COUNT -gt 5 ]]; then
                postqueue -p | less
        else
                postqueue -p
        fi
        ;;
show)
        echo $2
        postcat -q $2 | less
        ;;
flush)
        postqueue -c /etc/postfix -f
        ;;
purge)
        postsuper -d ALL
        ;;
start)
        #systemctl start postfix
        postfix start
        ;;
stop)
        #systemctl stop postfix
        postfix stop
        ;;
*)
        echo "Usage: $0 {count|list|show|flush|purge|start|stop}"
        mailq | tail -n 1
        RETVAL=1
esac
exit $RETVAL