#!/usr/bin/perl
use Term::ReadKey;

$char='q';

while(1){
ReadMode ('cbreak');
if (defined ($ch = ReadKey(-1))){
  #input was waiting and it was $ch 
     if ($ch eq $char){exit(0);}
}else{
   # no input was waiting 
   #your program goes here 
   print "############################\n";
   select(undef,undef,undef,.01);

}
ReadMode ('normal'); # restore normal tty settings 
}
__END__