If I have a file called canción, without any extension, and I want to
rename it to poesía, without extension, it doesn't do it.
The file canción remains the same.

Also if you have a file, say ola.txt, and you want to convert it to
mas.txt, it won't do it. It only works if the filename has at least 8
characters including point and extension.
Moreover, if the $to filename, has equal or more number of characters
than the $from filename and this has at least 10 characters, strange
characters appear on the $to filename.

For example if I want to convert television to publishing I get
publishing尀⩷␩)ꡀⅦ

You need to post your code ( How do I post a question effectively? )

You can see my code at Re^5: rename to UTF8 filename

I've already posted my code at the beginning of this thread:

#!perl

use utf8;

my $directory = '.';
opendir (MYHANDLE , $directory) || die "Cant open directory :$!\n";
my @files = readdir MYHANDLE;
closedir MYHANDLE;
foreach (@files) {
  my $original = $_;
  s/canción/poesía/;
  rename "$directory\\$original", "$directory\\$_";
}
[download]

And GrandFather proposed this code:

use strict;
use warnings;
use utf8;
use Win32::API;

my $moveFile = Win32::API->new("Kernel32", MoveFileW => 'PP', "I");
my $to       = 'poesía';
my $from     = 'canción';

$moveFile->Call(Encode::encode("UTF-16LE", $from),
    Encode::encode("UTF-16LE", $to));
[download]

which doesn't work for the reasons explained in my previous message.