nlm_local_shrlock
(void) nlm_local_shrlock(vp, &shlk, cmd, flags);
error = nlm_local_shrlock(vp, shr, cmd, flags);
static int nlm_local_shrlock(vnode_t *, struct shrlock *, int, int);
(void) nlm_local_shrlock(vp, shr, F_UNSHARE, FREAD | FWRITE);