A simple method is to use IO::Select to watch over the handle. The example below watches STDIN and waits for 5 seconds for a read before passing on.

By playing with parameters you can change the wait time, or make the code wait permanently. Also, by using IO::Handle or the like, you can read in individual characters, instead of whole lines. 

#!/usr/bin/perl

use IO::Select;

my $select = IO::Select->new();

$select->add(\*STDIN);
my @ready;

while(1) {
        if(@ready = $select->can_read(5)) {
                foreach (@ready) {
                        my $line = <$_>;
                        print "Read $line\n";
                }
        } else {
                print "5 seconds passed without a read\n";
        }

}

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$japh->{'Caillte'} = $me;

In reply to Re: Reading a line from file only when there is a new line (live) by Caillte
in thread Reading line from file only when there is a new line (live) by Anonymous Monk

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