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    1: 
    2: The "split" format is for a separating the gui from the main program.
    3: The main program can be installed setuid, and you don't want to link a
    4: gui-library with a setuid program.
    5: 
    6: 
    7: The split format is:
    8: 
    9: <pos> <host> <loss%> <rcvd pckts> <sent pckts> <best> <avg> <worst> 
   10: 
   11: 
   12: The "raw" format is:
   13: 
   14: hostline|pingline|dnsline|timestampline
   15: 
   16: hostline:
   17: h <pos> <host IP>
   18: 
   19: pingline:
   20: p <pos> <pingtime (ms)>
   21: 
   22: dnsline: 
   23: d <pos> <hostname>
   24: 
   25: timestampline:
   26: t <pos> <pingtime> <timestamp>
   27: 
   28: 
   29: Timestampline is not  yet implemented. Need to find out how to do
   30: ICMP timestamping first. :-)
   31: 
   32: 
   33: Someone suggested to put the following text here. As to context: Some
   34: people are wondering why mtr sometimes reports hosts beyond the
   35: destination host. 
   36: 
   37: 
   38: The FINAL host will occasionally be mentioned at position n, n+1, n+2
   39: etc.
   40: 
   41: You know traceroute, right? It sends a packet, waits for the reply to
   42: come back and when it comes back, it sends the next packet.
   43: 
   44: If say hosts 5-8 do not send "time exceeded" packets, you'll wait a
   45: 4*3 = twelve seconds extra before you get any results on hosts 9 and
   46: further. MTR doesn't work like that.
   47: 
   48: In theory we could send out a probe for host 1-40 all at once. But
   49: this would pose an unnecessary burden on the network. So what we do,
   50: is we send out probes for a max of 5 hosts beyond where we've seen a
   51: reply. So in the example above, we'd see a reply from router at
   52: position 4, then we'd send out 5-9 (and because the max-host is now at
   53: 9, we'll send them out at 1s/9 = 111ms intervals). When the reply from
   54: host 9 comes back, we'll start probing for host 10-15 (at about 60ms
   55: intervals). But suppose the network delay upto host 9 is already 200ms
   56: and suppose our destination host is at position 11. Then by the time
   57: the packet from host 11 comes back, we'll already have sent probe
   58: packets for position 12, 13, and 14! Those will come back as
   59: "destination reached" and be reported by the "raw" mode.
   60: 
   61: Curses mode will stop showing hosts with position numbers beyond the
   62: first reply of the destination host. It could gather the information
   63: about replies to packets sent as probes FURTHER than it actually is
   64: into the line displayed at its true position, but it doesn't (yet).
   65: 
   66: In fact the above example is almost completely true:
   67: 
   68: % mtr -r -n -c 2 152.179.99.218 | tail -5
   69:  13.|-- 144.232.18.238 0.0% 2 94.8 95.4 94.8 96.0 0.8
   70:  14.|-- 152.63.16.182 0.0% 2 95.1 95.5 95.1 95.8 0.5
   71:  15.|-- 152.63.64.106 0.0% 2 163.9 163.9 163.9 164.0 0.1
   72:  16.|-- 152.63.50.89 50.0% 2 163.7 163.7 163.7 163.7 0.0
   73:  17.|-- 152.179.99.218 50.0% 2 168.2 168.2 168.2 168.2 0.0
   74: % mtr -l -c 2 152.179.99.218 | grep -v "^[dp]" |tail -7
   75: h 10 144.232.1.41
   76: h 11 144.232.4.96
   77: h 16 152.179.99.218
   78: h 17 152.179.99.218
   79: h 18 152.179.99.218
   80: h 12 144.232.18.238
   81: h 13 152.63.16.182
   82: 
   83: As you can see we get the reply from the destination host at position
   84: 16 AFTER we've sent probes for position 17 and 18. When those come
   85: back, they are reported. That's what raw mode does. It reports the raw
   86: information.
   87: 
   88: If you write a backend for the raw mode, it's up to you to
   89: filter/display the results.
   90: 
   91: h 10 144.232.1.41
   92: h 11 144.232.4.96
   93: h 12 144.232.18.238
   94: h 13 152.63.16.182
   95: h 14 152.63.64.106
   96: h 15 152.63.50.89
   97: h 16 152.179.99.218
   98: h 17 152.179.99.218
   99: h 18 152.179.99.218
  100: