ref: bcc5530dab33d4603c421ae31be64d2ff3be7ec5
dir: /sys/lib/sysconfig/auth/files/rewrite/
# convert source domain address to a chain a@b@c@d... @([^@!,]*):([^!@]*)@([^!]*) alias \2@\3@\1 @([^@!]*),@([^!@,]*):([^!@]*)@([^!]*) alias @\1:\3@\4@\2 # convert a chain a@b@c@d... to ...d!c!b!a ([^@]+)@([^@]+)@(.+) alias \2!\1@\3 ([^@]+)@([^@]+) alias \2!\1 # all mail plan9\.bell-labs\.com!(.*) | "/mail/lib/qmail '\s' 'net!plan9\.bell-labs\.com'" "'\1'" .* | "/mail/lib/qmail '\s' 'net!plan9\.bell-labs\.com'" "'&'"