I am trying to figure out how to implement threads to ping about 10-20 hosts at a time. Win32(XP) Perl v5.8.0 built for MSWin32-x86-multi-thread 
use threads;
use threads::shared;
use strict;
my $wait = 500; my @up: shared; my $th;
my @down: shared;

my @list = qw ( www.apple.com www.perl.org www.ibm.com www.coke.com ww
+w.oracle.com www.hp.com );


foreach(@list){
$th = threads->create("ping","$_");
# $th->join;   # new thread is NOT created until join
               # not what I want!
}

# This works... unless one of the threads finishes too
# soon... then the app dies...

$th->join;

print @up;
print @down;

sub ping {
 my $ip = shift;
 my @rv = `ping -n 1 -w $wait $ip`;
 foreach(@rv){ push @up, "$ip up\n" if /\(0% loss\)/;
    push @down, "$ip down\n" if /\(100% loss\)/; }
}

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Ok, the problem is that if I join in the block where the threads get created... it waits for each process to finish. If I join after the create threads... it works... BUT ONLY IF all the threads finish in order... And, if I don't join at all... I don't get anything I have tried the async method, and got the same results. Are all the threads dependant on each other? If you have to wait on each thread to finish... what is the use in threads?

In reply to Using threads with Ping by JamesNC

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