#!/usr/bin/perl
use warnings;
use strict;
use IO::Select;

# remember what select says about mixing 
# buffered reading and "select", so even though the 
# code works, you might want to substitute 
# the read via <$fh> with:
#    my $input;
#    sysread( $fh, $input, 1024);


# loop every 5 second
my $timeout = 5;

my $s = IO::Select->new();
$s->add( \*STDIN );

while (1) {
    if ( my @ready = $s->can_read($timeout) ) {

        # we got input

        for my $fh (@ready) {
            print "$fh\n";
            my $input = <$fh>;
            print "got: $input";
        }
    }
    else {

        # no input
    }

    # just to show that we're looping
    print scalar localtime,"\n";
}