Use dh(1) for very short debian/rules.
#!/bin/sh
# postinst script for mercurial-server
#
# see: dh_installdeb(1)
set -e
# summary of how this script can be called:
# * <postinst> `configure' <most-recently-configured-version>
# * <old-postinst> `abort-upgrade' <new version>
# * <conflictor's-postinst> `abort-remove' `in-favour' <package>
# <new-version>
# * <postinst> `abort-remove'
# * <deconfigured's-postinst> `abort-deconfigure' `in-favour'
# <failed-install-package> <version> `removing'
# <conflicting-package> <version>
# for details, see http://www.debian.org/doc/debian-policy/ or
# the debian-policy package
case "$1" in
configure)
if ! getent passwd hg >/dev/null; then
adduser --disabled-password --quiet --system \
--shell /bin/sh --group \
--home /var/lib/mercurial-server \
--gecos "Mercurial repositories" hg
su -c "/usr/share/mercurial-server/init/hginit /usr/share/mercurial-server" hg
fi
;;
abort-upgrade|abort-remove|abort-deconfigure)
;;
*)
echo "postinst called with unknown argument \`$1'" >&2
exit 1
;;
esac
# dh_installdeb will replace this with shell code automatically
# generated by other debhelper scripts.
#DEBHELPER#
exit 0