#! perl -sw
use strict;
use threads;
use threads::shared;

my $sem: shared;

my $thr = threads->new(\&sub1);
sub sub1 {
    while(1){
        lock $sem;
        print "THREAD: in da zone !! :) \n";
        sleep 1;
    };
}

while(1){
    lock$sem;
    my $stuff='';
    read STDIN , $stuff,10;
    print "MAIN:", $stuff , "\n" ;
}