- oldfd = find234(fds, newfd, NULL);
- if (oldfd) {
- uxsel_input_remove(oldfd->id);
- del234(fds, oldfd);
- sfree(oldfd);
+ if (rwx) {
+ newfd = snew(struct fd);
+ newfd->fd = fd;
+ newfd->rwx = rwx;
+ newfd->callback = callback;
+ newfd->id = uxsel_input_add(fd, rwx);
+ add234(fds, newfd);