GROW
__slbexpand(fp, (len + GROW) * sizeof(wchar_t))) {
ATF_REQUIRE(ftruncate(c.fd, FSIZE + GROW) == 0);
ATF_REQUIRE((map = mmap(NULL, GROW, PROT_READ | PROT_WRITE,
arc4random_buf(map, GROW);
while (nread < GROW && (n = SSL_read_b(c.cln, buf, sizeof(buf))) > 0) {
ATF_REQUIRE(nread == GROW);
require_sbytes(&c, FSIZE + GROW);