strcmp_null
strcmp_null(pnm->last->unixname, nm->unixname) == 0 &&
strcmp_null(pnm->last->winname, nm->winname) == 0 &&
strcmp_null(pnm->last->windomain, nm->windomain) == 0) {
strcmp_null(user, namemaps.user) != 0 ||
strcmp_null(passwd, namemaps.passwd) != 0 ||