length() by default counts bytes, even if you have multibyte characters (UTF8/unicode) in your file.

For unicode lines to be counted correctly you need to open the file you are about to read with "encoding(UTF-8)" and if you want to print it out, you need to use "use utf8;" pragma.

#!/usr/bin/perl
use utf8;
use Encode;
use strict;
use warnings;

open(FF, "<:encoding(UTF-8)",'unicode.txt');
while(<FF>){
        chomp;
        my $l = length($_);
        my $str = "linenr=$. length=$l $_ \n";
        if(utf8::is_utf8($str)){
                # get rid of the wide character warning
                print encode('utf-8', $str); 
        }else{
                print $str;
        }
}
close(FF);

[download]

Now it could be your file is encoded in something else than UTF8 (like UTF16), so this might not be your solution yet.

See also how-do-i-find-the-length-of-a-unicode-string-in-perl

edit note: Edited the response to be more precise, as Choroba suggested.

In reply to Re: how to find the length of any line of file by FreeBeerReekingMonk
in thread how to find the length of any line of file by lakshmikant

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