rem: status = EOPNOTSUPP;
add: pos = ESPIPE;
context: user_seek(int fd, off_t pos, int seek_type){	struct file_descriptor *descriptor;	int status;	descriptor = get_fd(get_current_io_context(false), fd);	if (!descriptor)		return EBADF;	if (descriptor->ops->fd_seek)		status = descriptor->ops->fd_seek(descriptor, pos, seek_type);	else		status = EOPNOTSUPP;	put_fd(descriptor);	return status;}