#!/bin/bash
# trimmailbox - A simple script to ensure that only the four most recent
#    messages remain in the user's mailbox. Works with Berkeley Mail
#    (aka Mailx or mail): will need modifications for other mailers!

setvar keep = '4'  # by default, let's just keep around the four most recent messages

setvar totalmsgs = "$(echo 'x' | mail | sed -n '2p' | awk '{print $2}')"

if test $totalmsgs -lt $keep  {
  exit 0          # nothing to do
}

setvar topmsg = """$(( $totalmsgs - $keep ))"

mail > /dev/null <<< """
d1-$topmsg
q
"""

exit 0