setrctl
rc = setrctl(limit, NULL, rblk, 0);
return (setrctl(rname, old_blk, new_blk, rflag));
if (setrctl("task.max-lwps", NULL, blk, RCTL_INSERT) != 0)
extern int setrctl(const char *, rctlblk_t *, rctlblk_t *, int);