this code will keep running until enter is pressed and then continue running.

continueUntilEnterKey.pl

while(){
  runUntilEnterPressed();
  enterWasPressed();
}

sub runUntilEnterPressed{
  my $input;
  my $select_object = IO::Select->new(); $select_object->add(\*STDIN);
  my $sleep = .1;
  until($input){
    print doSomethingAwesome(); #thing to keep doing until enter is pressed
    if ($select_object->can_read($sleep ||.5)){$input = <STDIN>}
  }
  undef $input
}