Shell Programming and Scripting

Hello Everyone,

I'm a very new user to both NS-2 and awk and struggling quite a bit. I have a created a wireless trace in NS2 which is of the format as given below:

s 0.029290548 _1_ RTR --- 0 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
s 1.119926192 _0_ RTR --- 1 message 32 [0 0 0 0] ------- [0:255 -1:255 32 0]
M 10.00000 0 (5.00, 2.00, 0.00), (20.00, 18.00), 1.00
s 10.000000000 _0_ AGT --- 2 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
r 10.000000000 _0_ RTR --- 2 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
s 12.941172739 _1_ RTR --- 3 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
s 13.242656084 _0_ RTR --- 4 message 32 [0 0 0 0] ------- [0:255 -1:255 32 0]
s 16.000000000 _0_ AGT --- 5 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
r 16.000000000 _0_ RTR --- 5 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
s 24.799296167 _1_ RTR --- 6 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
s 27.719583723 _0_ RTR --- 7 message 32 [0 0 0 0] ------- [0:255 -1:255 32 0]
s 28.000000000 _0_ AGT --- 8 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
r 28.000000000 _0_ RTR --- 8 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
s 39.083332528 _1_ RTR --- 9 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
s 40.918940913 _0_ RTR --- 10 message 32 [0 0 0 0] ------- [0:255 -1:255 32 0]
M 50.00000 1 (390.00, 385.00, 0.00), (25.00, 20.00), 15.00
s 52.000000000 _0_ AGT --- 11 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
r 52.000000000 _0_ RTR --- 11 tcp 40 [0 0 0 0] ------- [0:0 1:0 32 0] [0 0] 0 0
s 53.478111556 _1_ RTR --- 12 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
s 54.709362820 _0_ RTR --- 13 message 32 [0 0 0 0] ------- [0:255 -1:255 32 0]
s 65.134134662 _1_ RTR --- 14 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
s 69.500212994 _0_ RTR --- 15 message 32 [0 0 0 0] ------- [0:255 -1:255 32 0]
r 69.501265756 _1_ RTR --- 15 message 32 [0 ffffffff 0 800] ------- [0:255 -1:255 32 0]
s 76.429530123 _1_ RTR --- 16 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
r 76.430622539 _0_ RTR --- 16 message 32 [0 ffffffff 1 800] ------- [1:255 -1:255 32 0]
s 76.430622539 _0_ RTR --- 2 tcp 80 [0 0 0 0] ------- [0:0 1:0 32 1] [0 0] 0 0
s 76.430622539 _0_ RTR --- 5 tcp 80 [0 0 0 0] ------- [0:0 1:0 32 1] [0 0] 0 0
D 76.430622539 _0_ IFQ ARP 2 tcp 80 [0 0 0 800] ------- [0:0 1:0 32 1] [0 0] 0 0
s 76.430622539 _0_ RTR --- 8 tcp 80 [0 0 0 0] ------- [0:0 1:0 32 1] [0 0] 0 0
D 76.430622539 _0_ IFQ ARP 5 tcp 80 [0 0 0 800] ------- [0:0 1:0 32 1] [0 0] 0 0
s 76.430622539 _0_ RTR --- 11 tcp 80 [0 0 0 0] ------- [0:0 1:0 32 1] [0 0] 0 0
D 76.430622539 _0_ RTR CBK 8 tcp 80 [0 0 0 800] ------- [0:0 1:0 32 1] [0 0] 0 0
D 76.430622539 _0_ RTR CBK 11 tcp 80 [0 0 0 800] ------- [0:0 1:0 32 1] [0 0] 0 0
s 81.503053035 _1_ RTR --- 17 message 32 [0 0 0 0] ------- [1:255 -1:255 32 0]
r 81.503945197 _0_ RTR --- 17 message 32 [0 ffffffff 1 800] ------- [1:255 -1:255 32 0]
s 83.261238775 _0_ RTR --- 18 message 44 [0 0 0 0] ------- [0:255 -1:255 32 0]
r 83.262226850 _1_ RTR --- 18 message 44 [0 ffffffff 0 800] ------- [0:255 -1:255 32 0]



I'm using an awk file in order to read the traces but I'm getting an error like "FATALivide by zero attempted"

I typed it in as "awk -f delay.awk simple.tr" ( I dunno if tht is right)

delay.awk
----------

Code:

BEGIN {highest_packet_id = 0;}
{
 action = $1;
 time = $2;
 node =$3;
 tracename = $4;
 type = $7;
 packet_id =$6;
 if (packet_id > highest_packet_id)
   highest_packet_id = packet_id;
 if (action == "s"){
 if (type == "cbr" && tracename == "AGT"){
    send_time[packet_id] = time;}
#else {send_time[packet_id] = 0;}
}
else if (action == "r"){
    if (type == "cbr" && tracename =="AGT"){
       rcv_time[packet_id] = time;
   }
#else{rcv_time[packet_id] = 0;}
 }
}
 END {packet_no = 0; total_delay = 0;
       for (packet_id = 0; packet_id <=highest_packet_id; packet_id++){
            if ((send_time[packet_id]!=0) && (rcv_time[packet_id]!=0)){
                start = send_time[packet_id];
                end = rcv_time[packet_id];
               packet_duration = end-start;}
else
      packet_duration = -1;
if (packet_duration > 0)
{packet_no++;
  total_delay = total_delay + packet_duration; }
}
   printf("%d %f %f\n", packet_no, total_delay, total_delay/packet_no);
}

Again I'm not sure if this is the right file to use, as it was mailed to me saying that I use this for delay. Should I make changes here ?? Should I use some other awk file ??? Should I make any other changes ??? Any help would be most welcome. Thank you so much for your time and help !!

In just trying to edit code tags, you seem to have several syntax errors. But the code is very hard to read. So who knows....

If you carefully describe what you are trying to do, then one of us can probably write simpler code that is readable to get you going. As it is I can't spend the time "decoding" your code.

Thank you so much for the reply Jim. I'm just trying to obtain the delay and overhead for the trace file here. Unfortunately I have no knowledge of how to work with awk, and how to parse the lines in the trace file. I used this awk file, as someone suggested it to me but its not of much help currently. If there's anything that can work better that would be fantastic. Once again, thank you so much for your time and help.