The fork call creates a duplicate of a process, called a child. This child can do whatever it likes, independantly to the parent (including using exec to replace itself with another program).

A very basic framework for what you're after might look like this (adapted from the code mentioned above in the Perl Cookbook):

#!/usr/bin/perl -w
use strict;

my @servers = qw(LIST OF SERVERS);

foreach my $server (@servers) {
    my $pid;
    next if $pid = fork;    # Parent goes to next server.
    die "fork failed: $!" unless defined $pid;

    # From here on, we're in the child.  Do whatever the
    # child has to do...  The server we want to deal
    # with is in $server.

    exit;  # Ends the child process.
}

# The following waits until all child processes have
# finished, before allowing the parent to die.

1 while (wait() != -1);

print "All done!\n";
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That should hopefully give you a good start on solving your problem. Don't hestiate to ask questions if anything doesn't make sense.

All the best,

Paul Fenwick
Perl Training Australia

sub bear_child {
   my $pid;
   my $sigset;

   # block signal for fork
   $sigset = POSIX::SigSet->new(SIGINT);
   sigprocmask( SIG_BLOCK, $sigset)
      or die "Can't block SIGINT for fork: $!\n";

   # fork a subprocess
   die "fork: $!" unless defined ($pid = fork);

   if ($pid) {
      # Parent records the child's birth and returns.
      sigprocmask( SIG_UNBLOCK, $sigset)
         or die "Can't unblock SIGINT for fork: $!\n";
      $children{$pid} = 1;
      $children++;
      return;
   } else {
      # Child process must *not* return from this subroutine.
      $SIG{INT} = 'DEFAULT';      # make SIGINT kill us as it did befo
+re
      # unblock signals
      sigprocmask( SIG_UNBLOCK, $sigset)
         or die "Can't unblock SIGINT for fork: $!\n";

      # do kid sutff
      # ...

      print "child $$ doing stuff\n";

      # cleanup

      print "child $$ is done processing\n";

      exit; # make sure sub never returns
   }
}
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-- Randal L. Schwartz, Perl hacker

I would like to propose a new acronym that could save everyone here a lot of typing:


CMFC

Check Merlyn's friendly colunms / check my friendly columns (if you are Merlyn)

()-()
 \"/
  `                                                     

Mr. Peabody Explains fork() is a great primer for understanding what fork does. I highly recommend it.

sigh...no article at that url...that thing about posting something on the internet makes it live forever? apparently not true for actually useful stuff. Will execute the Googleit routine.

http://wayback.archive.org/web/*/http://www.geeksalad.org/fork/all.html

I reckon we are the only monastery ever to have a dungeon stuffed with 16,000 zombies.

Learn to internet :)  [ddg://Mr. Peabody Explains fork()] Mr. Peabody Explains fork() -> Mr. Peabody Explains fork()

Abigail

Several people have built modules around fork, such as parallel::forkmanager or parallel::taskmanager can't remember names.

In your case, however, I think you just want to fork 150 times. Read the man page very closely, it takes a bit to wrap your mind around it.

____________________
Jeremy
I didn't believe in evil until I dated it.