They didn't give me a fork so I have to eat with a spawn.

[elwarren]

Since I don't have a working fork, this code will spawn a process in the background on win32. It is specifically setup to run one of my perl scripts with a few different config files and without a dos window. I drop this in my startup folder and it kicks them off with a 2 second delay between them (the spawned script monitors databases, I don't want to pound the machine with 5 connections all at once...)

#!/usr/bin/perl

use strict;
use warnings;
use Win32::Process;
use Win32;

my $sleep  = shift || 2;
my $pl     = "traydb.pl";
my $pldir  = "C:\\perl\\code\\TrayDb\\";
my @plargs = ('-configfile bdprod.cfg',
              '-configfile fdprod.cfg',
              '-configfile vdprod.cfg',
              '-configfile fddvlp.cfg',
              '-configfile bddvlp.cfg');

sub ErrorReport{
    print Win32::FormatMessage( Win32::GetLastError() );
}

sub SpawnTrayDb {
    my $ProcessObj = shift;
    my $pl = shift;
    my $plargs = shift;
    Win32::Process::Create($ProcessObj,
    "c:\\perl\\bin\\perl.exe",
    "perl $pl $plargs",
    0,
    DETACHED_PROCESS, 
    $pldir)|| die ErrorReport();
}

foreach (@plargs) {
    print "$pl $_\n";
    sleep $sleep;
    SpawnTrayDb(my $po, $pl, $_);
}

[bart]

Win32's Perl 5.6.1 does have an emulated fork(), though. Is there something wrong with that?

[RMGir]

Win32's Perl 5.6.1 does have an emulated fork(), though. Is there something wrong with that?

Yup.

If you try to fork and "spawn" off a bunch of system() calls, you get "Resource temporarily unavailable" after some fairly small number of forks (maybe 20?).

With Win32::Process::CreateProcess, you don't run into that problem.
--
Mike

[bart]

Good call.

BTW you should look into using $^X instead of the hardcoded path to perl.

[Anonymous Monk]

will the parent process have to wait until the child complete?

[elwarren]

I've never had much luck with ActiveState's fork. I don't even consider using it when I'm on win32. Most of my problems have been related to sockets. When a daemon accepts a connection and forks off, the socket doesn't have anything to say until the process dies. A socket that doesn't pass data isn't much use to me.

So I just keep the servers on the servers on client stuff like this on my workstation.

This code is more usefull for launching perl code without a dos window though, and that's why I wrote it. With this you don't have to bother hiding your dos parent in your code, it's already gone.