fsetfd_locked
static void fsetfd_locked(struct filedesc *fdp, struct file *fp, int fd);
fsetfd_locked(fdp, NULL, newfd);
fsetfd_locked(fdp, NULL, newfd);
fsetfd_locked(fdp, NULL, newfd);
fsetfd_locked(fdp, fp, new);
fsetfd_locked(fdp, fp, fd);