I have this sub to prompt the user for a response.
I'd like to have something like this that times out, what's good way of doing that? 


sub yn {
        my $question = shift; 
        $question ||='Your answer? ';

        my $val = undef;

        until (defined $val){
                print "$question (y/n): ";
                $val = <STDIN>;
                chomp $val;

                # $val = 
                #   $val eq 'y' ? 1 : (
                #      $val eq 'n' ? 0 : undef 
                #   );

                if ($val eq 'y'){ 
                   $val = 1; 
                }

                elsif ($val eq 'n'){ 
                   $val = 0;
                }

                else { 
                   $val = undef; 
                }
        }
        return $val;
}

[download]

(I guess what I'm missing is some kind of a counter, because the thing hangs waiting for stdin forever.. Maybe I could force to read stdin every 1 second, and thus I can count time.. but that would possibly yank the user's input before they concede, which is brutal. hmm.. )

I want to use this in tests, so that if there's no human being I can go on as needed. Are there some special precautions I should take when retrieving user input in my tests? I know they're picky about stdout (Test::Simple), right?

I want to optionally conduct intrusive tests (for example connecting to a database during testing ), defaulting to no.

update
This look interesting too, will test if the script was called via the command line? 

# from http://pleac.sourceforge.net/pleac_perl/userinterfaces.html
sub I_am_interactive {
    return -t STDIN && -t STDOUT;
}

[download]
Is there a major CAVEAT? Like, only runs on POSIX (muahhaha)? Is this kind of check reliable?

In reply to prompt and timeout in tests by leocharre

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