socket_accept
extern int socket_accept(struct sonode *, int, struct cred *, struct sonode **);
return (socket_accept(so, fflag, CRED(), nsop));
error = socket_accept(so1, 0, CRED(), &nso);
error = socket_accept(so, fp->f_flag, CRED(), &nso);
error = socket_accept(KSTOSO(ks), KSOCKET_FMODE(ks), cr, &nso);