readline() on closed filehandle $LISTDEL at ./delete_list_ver3.pl line 12 (#1)
    (W closed) The filehandle you're reading from got itself closed sometime
    before now.  Check your control flow.

##</code><code>##

#!/usr/bin/perl 
use strict; 
use warnings; 
use diagnostics; 

if (@ARGV = 2){ 
    my %delList;  
    open my $BEEPON, '>>', "./beepon.file"; 
    open my $BEEPOFF, '>>', "./beepoff.file"; 
    open my $LISTDEL, '<', $ARGV[0]; 
    
    foreach (<$LISTDEL>){ 
        chomp($_);
        $delList{$_} = 1; 
    } 
     
    open (my $ORGLIST, '<', $ARGV[1]); 
    
    foreach my $entry (<$ORGLIST>){ 
        chomp($entry);
        print { exists $delList{$entry} ? $BEEPON : $BEEPOFF } $entry . "\n";
    }

close $LISTDEL;
close $BEEPON; 
close $BEEPOFF; 
}