Your problem interests me :) AnyEvent will help you manage loops: 
use strict;
use warnings;
use AnyEvent;

my $file = 'my_file.txt';
my $cv = AnyEvent->condvar;

print "start editing $file ... Ľn";

# main loop
my $reader = AnyEvent->io(
    fh => \*STDIN,
    poll => 'r',
    cb => sub {
        system( 'vim', $file );
        if ( is_valid( $file ) ) {
            print "File is okĽn";
            $cv->send; # exits "main loop"
        }
        else {
            print "Hit return to continueĽn";
        }
    },
);

# enters "main loop" till $cv gets ->send
$cv->recv;

sub is_valid {
    # validate my_file.txt here
}

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In reply to Re: File handles and loops by anazawa
in thread File handles and loops by dr.jekyllandme

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