gitlab-org--gitlab-foss/bin/daemon_with_pidfile
Jacob Vosmaer 1081a322f1 Properly daemonize the mail_room process
The old invocation only worked by accident because we have a '&'
somewhere in the init script for expediency. When ran from a terminal,
the mail_room daemon process ended up in the session of the terminal.
This commit adds a small wrapper that tries to do the textbook
daemonization steps (double fork, setsid etc.) while also taking
care that the pidfile is written before the 'start' process exits.
2015-08-27 16:35:00 +02:00

33 lines
716 B
Ruby
Executable file

#!/usr/bin/env ruby
# daemon_with_pidfile
#
# Daemonize, write a pidfile, and exec the remainder of the command line.
def main(pidfile, cmd)
if middle_pid = Process.fork
# outer process
# Do not exit the outer process before the middle process finishes
Process.waitpid(middle_pid)
exit $?.exitstatus
end
if final_pid = Process.fork
# middle process
open(pidfile, 'w') { |f| f.puts final_pid }
exit
end
# Standard daemon things: become session leader, ignore SIGHUP, close stdin.
Signal.trap("HUP", "IGNORE")
Process.setsid
IO.new(0).close
exec(*cmd)
end
if ARGV.count < 2
abort "Usage: #$0 pidfile command [args...]"
end
pidfile = ARGV.shift
main(pidfile, ARGV)