Upstart script for haproxy with support for reload.

gistfile1.sh

description "Properly handle haproxy"

start on startup

env PID_PATH=/var/run/haproxy.pid
env BIN_PATH=/usr/sbin/haproxy

script
exec /bin/bash <<EOF
  $BIN_PATH -f /etc/haproxy.cfg -D -p $PID_PATH

  trap "$BIN_PATH -f /etc/haproxy.cfg -p $PID_PATH -sf \\\$(cat $PID_PATH)" SIGHUP
  trap "kill -TERM \\\$(cat $PID_PATH) && exit 0" SIGTERM SIGINT

  while true; do # Iterate to keep job running.
    sleep 1 # Don't sleep to long as signals will not be handled during sleep.
  done
EOF
end script

You're right, of course. There should be some sort of check for the pid-file in the while loop. $Something like kill -0 $(cat $PID_PATH) || exit 1 should do the trick (untested though).

There is one small bug here. The SIGHUP trap won't write out the new pid to the pid file without -D to daemonize. Anyways thanks for this, I adapted your gist to runit and it properly responds to reload, restart, etc.

Need to check with nbproc >1 and -Ds option to stay in foreground in "systemd daemon mode".
If pidfile still created, we can use shell builtin wait instead of sleep 1.

In shells I saw so far wait is interrupted by SIGHUP and the signal handler is executed