I suspect it has to do with the threads object's lexical scoping and perl's garbage collector. I modified your code to below and it works -
#!/usr/bin/perl
use 5.008;             # 5.8 required for "stable" threading
use strict;
use warnings;
use threads;
use threads::shared;
use IO::SOCKET;
use Data::Dumper;

my @threads;
for (my $i = 0; $i < 5; $i++) {
    my $thread = threads->create(\&start_thread, "localhost:80");
    $thread->detach;
    push @threads, $thread;
}
sleep(2);
print STDERR "done\n";
exit;

sub start_thread {
   my $tid = threads->self->tid;
   print STDERR "Start $tid\n";
   sleep(1); # do something in the thread
   print STDERR "Finish $tid\n";
}

[download]
What I think is happenning is that threads->create creates a temporary object (in threads module, create is new), and this object goes out of scope at the end of the for block and Perl happily 'freed' it with the garbage collector. You have to make sure that the created threads object does not go out of scope to have it working properly.

In reply to Re: Activestate 5.8.2 broke my threads :( by Roger
in thread Activestate 5.8.2 broke my threads :( by Anonymous Monk

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