pinger

type Host struct {
	Address         string
	IsUp            bool
	UpDown          int // >1 up <-1 down 0=unknown
	PacketsSent     int
	PacketsReceived int
	Changes         int           // number of up->down or down->up transitions
	UpTime          time.Duration // total amount of time host has been up
	DownTime        time.Duration // total amount of time host has been down
	Interval        time.Duration // time between pings
	MaxRTT          time.Duration // rtt greater than this value will declare a host down
	Timeout         time.Duration // wait this long at most for a pong
	LastRTT         time.Duration // latest RTT value
	Stats           f64stat.Stat  // RTT stats.  min/ave/max/sdev
	C               chan string   // channel to send command to the pinger go routine

	//ltDown           time.Time     // time of start of last DOWN
	//downCount       int           // number of missed pongs
	DownThreshold int    // number of missed pongs to declare host down
	History       []*Rtt // RTT and message history
	HistoryMax    int    // Maximum size of history
	// contains filtered or unexported fields
}

type HostCallbackFunc func(h *Host, msg string, arg string)

type Pinger struct {
	Bind4         string
	Bind6         string
	PayloadSize   uint16
	Interval      time.Duration // default ping interval
	MaxRTT        time.Duration // default host down threshold
	DownThreshold int           // number of missed pongs to declare host down
	HistoryMax    int           // maximum size of history.  0=off
	// contains filtered or unexported fields
}

type Rtt struct {
	T      time.Time
	D      time.Duration
	UpDown int
	Err    error
	Msg    string
	Arg    string
}