2 - Another option is select ( perldoc -f select ).

The code below will give you 5 seconds to enter text on STDIN.
A higher level interface seems to be provided by IO::Select.

use strict;
use warnings;

my $seconds = 5;

my $rin = "";

vec( $rin , fileno( STDIN ) , 1 ) = 1;

my ( $found , $left ) = select( $rin , undef , undef , $seconds );

if( $left )
{
        print "you said " . <STDIN> . "\n";
}
else
{
        print "nothing to see\n";
}
[download]