package My::Tee;
use Tie::Handle;

our @ISA = qw[ Tie::Handle ];

sub TIEHANDLE {
    die "Usage: tie *STDxxx, 'My::Tee', 'logfilepath'"
        unless @_ == 2;

    open my $std, '>', 'CON'
        or die "Couldn't reopen STDxxx : $!"
        and return;

    my( $flush, $old ) = ( $|, select( $std ) );
    $| = $flush; select( $old );

    open my $log, '>', $_[1]
        or die "Couldn't open $_[1] for output: $!"
        and return;

    bless { log => $log, stdout => $std }, $_[0];
}

sub PRINT {
    my $self = shift;
    print { $self->{ log } } @_;
    print { $self->{ stdout } } @_;
}

sub PRINTF {
    my $self = shift;
    printf { $self->{ log } } @_;
    printf { $self->{ stdout } } @_;
}

1;
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