:0 Whc: vacation.lock
# Reply if mail is addressed to me.
# Don't reply to daemons or mailing lists.
# Avoid mail loops (don't reply to mail I might send myself).
* .*for <USER@DOMAIN>
* !^FROM_DAEMON
* !^X-Loop: USER@DOMAIN
# Store sender's address in vacation.cache if not there already.
| formail -rD 8192 vacation.cache
# If sender's address not in cache (e=previous recipe failed), send
# mail containing vacation message.  Note:  Trailing backslashes (\)
# required to denote continuation of single action line.
:0 ehc
 | (formail -rA"Precedence: junk" \
 -A"X-Loop: USER@DOMAIN" ; \
 cat $PMDIR/vacation.msg \
 ) | /usr/lib/sendmail -oi -t