#!/bin/bash

HOSTNAME=$1
RECIPIENT=$2
SENDER=$3
errex() {
  echo -e "$@" 1>&2
  exit 1
}

test -x /usr/sbin/pflogsumm || errex "Critical: /usr/sbin/pflogsumm not found"

# The case that the mail.log.1 file isn't readable shouldn't actually be possible with logrotate not rotating empty files.. But you never know!
if [ -r "/var/log/mail/mail.log.1" ]; then
  BODY=$(/usr/sbin/pflogsumm /var/log/mail/mail.log.1 --problems-first)
else
  BODY="Error: Mail log not readable or not found: /var/log/mail/mail.log.1

In case of mail inactivity since the last report, this might be considered a nuisance warning.

Yours faithfully,
The $HOSTNAME Mailserver"
fi

sendmail -t <<EOF
From: $SENDER
To: $RECIPIENT
Subject: Postfix Summary for $HOSTNAME
Content-Transfer-Encoding: 8bit
Content-Type: text/plain; charset=UTF-8

$BODY
EOF