$value = Z_STREAM_END() if $gz->eof() && $value == 0 ;
    }

    _set_gzerr($value) ;
}

sub gzopen($$)
{
    my ($file, $mode) = @_ ;

    my $gz ;
    my %defOpts = (Level    => Z_DEFAULT_COMPRESSION(),
                   Strategy => Z_DEFAULT_STRATEGY(),
                  );

    my $writing ;
    $writing = ! ($mode =~ /r/i) ;
    $writing = ($mode =~ /[wa]/i) ;

    $defOpts{Level}    = $1               if $mode =~ /(\d)/;
    $defOpts{Strategy} = Z_FILTERED()     if $mode =~ /f/i;
    $defOpts{Strategy} = Z_HUFFMAN_ONLY() if $mode =~ /h/i;
    $defOpts{Append}   = 1                if $mode =~ /a/i;

    my $infDef = $writing ? 'deflate' : 'inflate';
    my @params = () ;

    croak "gzopen: file parameter is not a filehandle or filename"
        unless isaFilehandle $file || isaFilename $file  || 
               (ref $file && ref $file eq 'SCALAR');

    return undef unless $mode =~ /[rwa]/i ;

    _set_gzerr(0) ;

    if ($writing) {
        $gz = new IO::Compress::Gzip($file, Minimal => 1, AutoClose => 1, 
                                     %defOpts) 
            or $Compress::Zlib::gzerrno = $IO::Compress::Gzip::GzipError;
    }
    else {
        $gz = new IO::Uncompress::Gunzip($file, 
                                         Transparent => 1,
                                         Append => 0, 
                                         AutoClose => 1, 
                                         MultiStream => 1,
                                         Strict => 0) 
            or $Compress::Zlib::gzerrno = $IO::Uncompress::Gunzip::GunzipError;
    }

    return undef
        if ! defined $gz ;

    bless [$gz, $infDef], 'Compress::Zlib::gzFile';
}

sub Compress::Zlib::gzFile::gzread
{
    my $self = shift ;

    return _set_gzerr(Z_STREAM_ERROR())
        if $self->[1] ne 'inflate';

    my $len = defined $_[1] ? $_[1] : 4096 ; 

    if ($self->gzeof() || $len == 0) {
        # Zap the output buffer to match ver 1 behaviour.
        $_[0] = "" ;
        return 0 ;
    }

    my $gz = $self->[0] ;
    my $status = $gz->read($_[0], $len) ; 
    _save_gzerr($gz, 1);
    return $status ;
}

sub Compress::Zlib::gzFile::gzreadline
{
    my $self = shift ;

    my $gz = $self->[0] ;
    {
        # Maintain backward compatibility with 1.x behaviour
        # It didn't support $/, so this can't either.
        local $/ = "\n" ;
        $_[0] = $gz->getline() ; 
    }
    _save_gzerr($gz, 1);
    return defined $_[0] ? length $_[0] : 0 ;
}

sub Compress::Zlib::gzFile::gzwrite
{
    my $self = shift ;
    my $gz = $self->[0] ;

    return _set_gzerr(Z_STREAM_ERROR())
        if $self->[1] ne 'deflate';