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

sub nap { select '','','', $_[0] }

my $done:shared = 0;
my $thread = async( sub {
    $|++;
    until( $done ) {
        nap( 0.1 ),  printf "\r%s\t\t", '.' x $_ for 1 .. 10, reverse 1 .. 10;
        nap( 0.01 ), printf "\r%s\t\t", '.' x $_ for 1 .. 10, reverse 1 .. 10;
        nap( 0.8 );
    }
}, $done );

sleep 60;
$done = 1;
$thread->join;