use strict; use warnings;         # hallelujah
use threads; use threads::shared; # threads, oh how I hate

my $lockvar : shared = 0;
my $thrHandle = threads->create( &exampleSub );

{lock $lockvar;
cond_wait ($lockvar);}
# code that should be executed at the same time as the
# block below
$thrHandle->join();
sub exampleSub {
    # some initialisation which may, or may not, take a lot
    # of time
    {lock $lockvar;
    cond_signal( $lockvar );}
    # code that should be executed at the same time as the 
    # block above
}