gail@shell:~$ cat process.rules 
# RULES FOR GAIL THE SMAIL
# A tab-delimited handler for passing mail between gail and exim
#
# Format of file: inbound<TAB>outbound<TAB>header<TAB>keyword(s)
# For example:
# mbx	ssh	Subject	SECURITY
#
# Definitions:	mbx		ssh		rss	sms	web
#		Local Mail	Gail Transport	Specialty Functions
#
# Comments MUST have the symbol as the first character in each line

ssh	mbx	ALL	UNMATCHED

# Temporary setup
mbx	mbx	ALL	UNMATCHED

================

gail@shell:/home/joel$ incrontab -l
/var/mail/gail	IN_CLOSE_WRITE	~/trig-mbx.sh $@/$# >/dev/null
/var/spool/gail/inbox	IN_CLOSE_WRITE	~/trig-ssh.sh $@/$# >/dev/null

================

gail@shell:~$ cat trig-ssh.sh 
#!/bin/sh

NOW=$(date -u +%F-%H%M.%N)
sleep 2s
cp $1 ~/current/ssh-$NOW.txt
rm $1
~/process.sh ssh $NOW

================

gail@shell:~$ cat trig-mbx.sh 
#!/bin/sh

NOW=$(date -u +%F-%H%M.%N)
sleep 2s
cp $1 ~/current/mbx-$NOW.txt
rm $1
~/process.sh mbx $NOW

================

gail@shell:~$ cat process.sh 
#!/bin/bash

INCOM=$1
FILE="current/$1-$2.txt"

arrOUTs=()

# Check if any special rules exist
if [ $(grep -e "^$INCOM" process.rules | grep -v UNMATCHED | wc -l) -gt 0 ]; then

	# Create array for defined headings
	arrHeads=($(grep -e "^$INCOM" process.rules | grep -v UNMATCHED | cut -f 3 | sort | uniq))

	for idxHeads in ${!arrHeads[*]}; do
		arrValue=($(grep -e "^$INCOM" process.rules | grep -v UNMATCHED | grep "${arrHeads[$idxHeads]}" | cut -f 4 | sort | uniq))
		if [ ${#arrValue[*]} -eq 0 ]; then
			for idxValue in ${!arrValue[*]}; do
				if [ "${arrHeads[$idxHeads]}" == "ALL" ]; then
					TEST=$(grep "${arrHeads[$idxVaue]}" $FILE | wc -l)
				else
					TEST=$(grep "${arrHeads[$idxHeads]}:" $FILE | grep "${arrHeads[$idxHeads]}" | wc -l)
				fi
				if [ $TEST -ne 0 ]; then
					arrOUTs+=($(grep -e "^$INCOM" process.rules | grep "${arrHeads[$idxHeads]}" | grep "${arrValue[$idxValue]}" | cut -f 2 | sort | uniq))
				fi
			done
		fi
	done

fi

# Indiscriminately add any UNMATCHED rules
arrOUTs+=($(grep -e "^$INCOM" process.rules | grep UNMATCHED | cut -f 2 | sort | uniq))

# Handle outbounds individually

#mbx
if [ $(echo "${arrOUTs[@]}" | grep "mbx" | wc -l) -gt 0 ]; then
	SENDADDR="joel@shell.node"
	HEADFROM=$(grep -e '^From:' $FILE | head -1)
	HEADSUBJ=$(grep -e '^Subject:' $FILE | head -1 | sed 's/[\*\?]//g')
	GAILSUBJ=$(echo "$HEADSUBJ"|sed 's/^Subject:/Relay:/')
	HEADDATE=$(grep -e '^Date:' $FILE | head -1)
	printf "%s\\n" "$HEADFROM" "$HEADSUBJ" "$HEADDATE" "" "$(cat $FILE | sed '0,/^$/d')" | mail -s "$GAILSUBJ" -- $SENDADDR
fi

# Cleanup
mv $FILE outbox/
find outbox/ *.txt -mtime +7 -type f -prune -exec rm {} \;