func (m *MACMaskArg) MarshalBinary() ([]byte, error) {
	// Must indicate correct number of directives
	if int(m.DirCount) != len(m.Directives) {
		return nil, ErrorBadArgumentParameter
	}

	// Allocate byte slice for argument and all directives
	b := make([]byte, macMaskArgLen+(directiveLen*m.DirCount))

	// 1 byte reserved

	b[1] = uint8(m.Command)
	b[2] = uint8(m.Error)
	b[3] = m.DirCount

	// Marshal each directive into binary and copy into byte slice
	// after argument
	n := 4
	for _, d := range m.Directives {
		db, err := d.MarshalBinary()
		if err != nil {
			return nil, err
		}

		copy(b[n:n+directiveLen], db)
		n += directiveLen
	}

	return b, nil
}
func (m *MACMaskArg) MarshalBinary() ([]byte, error) {
	// Must indicate correct number of directives
	if int(m.DirCount) != len(m.Directives) {
		return nil, ErrorBadArgumentParameter
	}

	// Allocate byte slice for argument and all directives
	b := make([]byte, macMaskArgLen+(directiveLen*m.DirCount))

	// 1 byte reserved

	b[1] = uint8(m.Command)
	b[2] = uint8(m.Error)
	b[3] = m.DirCount

	// Marshal each directive into binary and copy into byte slice
	// after argument
	n := 4
	for _, d := range m.Directives {
		db, err := d.MarshalBinary()
		if err != nil {
			return nil, err
		}

		copy(b[n:n+directiveLen], db)
		n += directiveLen
	}

	return b, nil
}
// MarshalBinary allocates a byte slice containing the data from a MACMaskArg.
//
// If m.DirCount does not indicate the actual length of m.Directives, or
// a Directive is malformed, ErrorBadArgumentParameter is returned.