unparse_time
unparse_time(t, str, len);
unparse_time (val, buf, sizeof(buf));
unparse_time(*ent.max_life, t, sizeof(t));
unparse_time(*ent.max_renew, t, sizeof(t));
sz = unparse_time(tests[i].val, NULL, 0);
sz = unparse_time(tests[i].val, buf, buf_sz);
sz = unparse_time(tests[i].val, buf, min(buf_sz, tests[i].size));
unparse_time (int t, char *s, size_t len);