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Hi, I'm trying to port a complex application from FreeBSD to Win32, and am having all kinds of problems with starting and stopping processes. Before getting into specific questions, let me describe the program. Perhaps someone has some general guidelines or ideas for starting and stopping this monster.

SUPERVISOR.PL
-------------
  print PIDFILE "$$\r\n";

  $SIG{QUIT} = \%SHUTDOWN;

  fork()
  if child, exec ctrlman.pl
  fork()
  if child, exec pidman.pl
  fork()
  if child, exec progman.pl
  fork()
  if child, exec webman.pl
  while (1) {
    do stuff
  }
  exit;

  sub SHUTDOWN {
    kill 3, CTRLMAN_pid   # pid saved from the fork
    kill 3, PIDMAN_pid
    kill 3, PROGMAN_pid
    kill 3, WEBMAN_pid
  }
[download]

Supervisor and his four children then talk to each other through DGRAM sockets. One big happy family.

Each programX has its own SHUTDOWN - SIG{QUIT} handler - which does an orderly shutdown, closing sockets and things before exiting.

In freeBSD:
I start with csh> perl supervisor.pl
I stop with csh> kill -3 `cat PIDFILE`
The supervisor propagates the QUIT to the other processes, and everybody shuts down nicely.

19:28:39:982 SUPERVISOR: Shutdown started^M
19:28:39:983 SUPERVISOR: Killing Ctrlman Pidman Progman Webman^M
19:28:39:983 SUPERVISOR: Waiting for processes to die^M
19:28:39:984    CTRLMAN: Shutdown started^M
19:28:39:985    CTRLMAN: Shutdown complete^M
19:28:39:990     PIDMAN: Shutdown started^M
19:28:39:991     PIDMAN: Shutdown complete^M
19:28:39:994    PROGMAN: Shutdown started^M
19:28:39:995    PROGMAN: Shutdown complete^M
19:28:39:997     WEBMAN: Shutdown started^M
19:28:39:998     WEBMAN: Shutdown complete^M
19:28:40:001 supervisor: reaped 17752 exit 0 signal 0 dump 0^M
19:28:40:002 SUPERVISOR: Shutdown complete^M
[download]

Everything works so nicely in Unix...

NOT so in Win32.
Windows doesn't really have signals or signal handlers, so the whole signal idea pretty much goes out the window (pun intended), although PERL does implement some limited signal handling capabilities.

If anyone has some general suggestions for managing startup and shutdown of such a system, I'd be glad to hear them.

I've got a ton of questions, so point me in the right direction now, and save yourself a ton of questions later.

Thanks,
Dave

In reply to Win32: Starting and stopping processes (part 1) by hennesse

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