Function wait_pid_gone

tests/test_subprocess.c:306–317

}

static bool wait_pid_gone(pid_t pid, int timeout_ms) {
    uint64_t deadline = cbm_now_ms() + (uint64_t)timeout_ms;
    do {
        errno = 0;
        if (kill(pid, 0) < 0 && errno == ESRCH) {
            return true;
        }
        subprocess_test_pause();
    } while (cbm_now_ms() < deadline);
    errno = 0;
    return kill(pid, 0) < 0 && errno == ESRCH;
}

/* Best-effort cleanup for a failing implementation, so a red tree test does not
 * leave its TERM-ignoring probes behind for later tests. The production API must