*** I know I've posted this twice, because the question was duplicated and I didn't know which one would get reaped. If this is against etiquette, please /msg me.

Here's some example code with the fork()'s in place: 

#! /usr/bin/perl -w

use strict;

$SIG{CHLD} = \&REAPER;
my @server_list = qw/one two three four/;
my $children = 0;

foreach my $server (@server_list) {
  print "$$ Forking for server: $server\n";
  if (my $pid = fork) {
    # Parent process
    # Nothing to do except go to the next server in the list
    $children++;
    sleep 2;
    next;
  } else {
    # Child process
    # Note that you *must* use 'exit;' when processing is
    # finished or the child will continue going through the
    # loop
    print "$$ Processing for server: $server\n";
    sleep 3;
    exit;
  }
}


# Wait for children to finish
while ($children > 0) {
  sleep;
}

sub REAPER {
  my $pid = wait;
  print "Process $pid has done it's stuff!\n";
  $children--;
}

[download]
When a forked process dies, the parent process will get a SIGCHLD signal (I am assuming you are using UNIX). Unless the parent does something with this signal, the child process will becoma a 'zobmie', and eventually the process table will fill up (not good). If you don't need to keep track of the children as they finish, do $SIG{CHLD} = 'IGNORE'. I've put some delays in the example code so you can see this happening.

You should also be aware that as with any system call, a fork() can fail. Read page 715 of 'Programming Perl, 3rd edition' for more info.

JJ

In reply to Re: simoultaneous connections using Net::SSH::Perl by jj808
in thread simoultaneous connections using Net::SSH::Perl by vxp

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