Dear Monks, I am learning Curses and Threads, as a simple exercise I have written below code to update a dummy counter at a given row. Program works fine for some time and suddenly the terminal screen starts displaying all weird characters. Please help me to understand the concept I have missed. 
use threads;
use Curses;
use strict;

initscr();
curs_set(0);

box( ACS_VLINE, ACS_HLINE );

my $lthr = threads->create(\&counter, 5);
my $rthr = threads->create(\&counter, 15);

sub counter {
    my $pos = shift; #Position:Row
    my $lctr = 0;
    while(1) {
        $lctr++;
        move($pos,5);
        addstr("$lctr");
        napms(100);
        refresh();
    }
}

$lthr->join();
$rthr->join();

getch();
endwin();
exit(0);

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In reply to Weird Output with Threads and NCurses by var121

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