holdsock
if ((error = holdsock(td, fd, &fp)) == 0) {
error = holdsock(td, s, &fp);
error = holdsock(td, s, &fp);
error = holdsock(td, s, &fp);
error = holdsock(td, s, &fp);
error = holdsock(td, s, &fp);
error = holdsock(td, sfd, &fp);
error = holdsock(td, s, &fp);
error = holdsock(td, s, &lfp);
error = holdsock(td, s, &fp);
error = holdsock(td, s, &fp);
error = holdsock(td, s, &fp);
int holdsock (struct thread *td, int fdes, struct file **fpp);
error = holdsock(td, nfsdarg.sock, &fp);