Listing 2. mailage.sh Script

#!/bin/bash
# mailage.sh - Process each message and keep it 
# or discard it.
MAILDATE=/usr/local/bin/maildate.sh
# Write rest of message to output
function writerest () {
	echo "$from $address $dayofweek $month "
	echo "$dayofmonth $time $timezone $year"
	cat -
	# If your cat is broken and doesn't echo 
	# lines faithfully then comment
	# the _cat_ line above and uncomment the 
	# following four lines
	#	while read -r inputstring
	#	do
	#		echo $inputstring
	#	done
}

# keepdate = integer representation of date before 
# which to discard
keepdate=$1
read -r from address dayofweek month dayofmonth \
	time timezone year

# If formail had to fix the message date, there's 
# no time zone in it.
if [ X"$year"X = XX ]
then
	year=$timezone
	timezone="GMT"
fi

msgdate=`$MAILDATE $month $dayofmonth $year`

if [ $? -le 1 ] # Parsing OK
then
	# Recent message
	if [ $msgdate -gt $keepdate ] 
	then
		writerest
	fi

# Error in date parsing; save message
else
	writerest
fi