In this script, I get the error "Illegal modulus zero," but I can't see why it says that. Any ideas?
use strict;
use warnings;

if(!@ARGV){
    my $line=1;
    $_=<>;
    handlefix();
    open(INFILE, '<', $_) or die "\nCan't open $_: $!\n";
    $_=<>;
    handlefix();
    open(OUTFILE, '>', $_) or die "\nCan't open $_: $!\n";
    while(<INFILE>){
        print OUTFILE "_$line",":     $_" if $line %% 5==0;
        print OUTFILE "         $_" if $line %% 5!=0;
        $line++;
    }   
    close INFILE && close OUTFILE;
}
if(@ARGV){
    my $line=1;
    $_= shift @ARGV;
    handlefix();
    open(INFILE, '<', $_) or die "\nCan't open $_: $!\n";
    $_= shift @ARGV;
    handlefix();
    open(OUTFILE, '>', $_) or die "\nCan't open $_: $!\n";
    while(<INFILE>){
        print OUTFILE "_$line",":     $_" if $line %% 5==0;
        print OUTFILE "         $_" if $line %% 5!=0;
        $line++;
    } 
    close INFILE && close OUTFILE;
}


sub handlefix {
    chomp($_);
    $_=~s/"//g;
    $_=~s/\//\\/g;
    return $_;
}

[download]

Thanks in advance!

In reply to Modulus by zero? by Andrew_Levenson

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