a_gid
gid = a_gid(cp);
build_iovec_argf(&iov, &iovlen, "gid", "%d", a_gid(optarg));
static gid_t a_gid(const char *);
static gid_t a_gid(char *);
gid = a_gid(optarg);
a_gid(cp);
a_gid(cp);
a_gid(*argv);
static void a_gid(const char *);