I don't think it is supported. The option you used is called discipline and that is perl 5.6 talk , that feature is now called PerlIO layers

Also, that feature is not documented in Tie::File ; And, in 5.6, that feature only supported :raw and :crlf, as :encoding did not exist ; You should file a bug report (did I say that?)

But you can work around this limitation by doing your own encoding/decoding. This seems to work 

#!/usr/bin/perl --
use Path::Class;
use constant THISFILE => file( __FILE__ )->absolute->stringify;
use constant THISDIR  => file( THISFILE )->dir->stringify;
use strict; use warnings;
use Tie::File;
use Fcntl 'O_RDWR', 'O_CREAT';
use Encode;
    
chdir THISDIR or die Fudge( 'chdir', THISDIR );

Main( @ARGV );
exit( 0 );

sub Main {
    binmode STDOUT;
    my $FileName = "".file( THISFILE . '.tf.utf8.txt' );
    tie
        my(@Tied),
        'Tie::File',
        $FileName,
        recsep => "\x0D\x0A",
        mode => O_RDWR | O_CREAT,
    or die Fudge( tie => $FileName );
    
    if( @Tied > 2 ){
        print 'size ', int @Tied, "\n";
        print map { decode('UTF-8', $_ ); "($_)" } @Tied;
    } else {
        push @Tied, encode('UTF-8', chr $_) for 272 .. 30000;
    }
    untie @Tied;
}


sub Fudge {
    use Errno();
    join qq/\n/,
      "Error @_",
      map { "  $_" } int( $! ) . q/ / . $!,
      int( $^E ) . q/ / . $^E,
      grep( { $!{$_} } keys %! ),
      q/ /;
}

__END__

[download]

So you might subclass it like this (untested)

package Tie::File::UTF8;
use parent qw[ Tie::File ];
sub TIEARRAY {
    my $class = shift;
    $class->SUPER::new(
        @_,
        recsep => "\x0D\x0A",
        discipline => ':raw',
    );
}
sub FETCH {
    my( $self, $n ) = @_;
    my $rec = $self->SUPER::FETCH( $n );
    $rec = decode( 'UTF-8', $rec );
    $rec;
}
sub STORE {
    my( $self, $n, $rec ) = @_;
    $rec = encode( 'UTF-8', $rec );
    $self->SUPER::FETCH( $n, $rec );
}

[download]

I don't know about more exotic encodings , but it seems UTF-8 could be supported easily

In reply to Re: Tie::File failing with Unicode/UTF-8 encoding? by Anonymous Monk
in thread Tie::File failing with Unicode/UTF-8 encoding? by HelenCr

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