docker-mailserver/target/bin/delmailuser

#! /bin/bash

DATABASE=${DATABASE:-/tmp/docker-mailserver/postfix-accounts.cf}

USER="$1"

usage() {
	echo "Usage: delmailuser <user@domain>"
}

errex() {
	echo "$@" 1>&2
	exit 1
}

escape() {
	echo "${1//./\\.}"
}

[ -z "$USER" ] && { usage; errex "No user specifed"; }
[ -s "$DATABASE" ] || exit 0

# XXX $USER must not contain /s and other syntactic characters
sed -i "/^$(escape "$USER")|/d" $DATABASE