"execution problem with perl"

Applications Programming
1

hi everyone,

before stating my problem ,
i just want to say
thanks in advance for the time and trouble taken:-)

i am an newbie to perl programming,
the problem is a text file needed to be parsed,
i have looked over regular expressions and string matching but coudnt helped out..
the text file contained the format:-

A,1,B
A,2,B
A,1,C
C,1_1,A
B,2,D
B,1_1,A
B,2_2,A
B,2_2,D

after doing the required parser, the output must be in the following format shown below

A,1,B
B,1_1,A
A,2,B
B,2_2,A
A,1,C
C,1_1,A
B,2,D
D,2_2,D

can anyone let me know how to get the above required format?

thanks
raghuraipur

2

Is there any logic behind the ordering in the input and output? Sorry, I don't see it... you might wanna be more specific -- you'll improve your chances of getting the help you need.
What features are you trying to parse upon?

3

thanks for replying mirni,

there is no logic in order, of input...
let us assume
A-source
1-message
B-destination..

so whenever we parse message, eg-1;
it should print all the messages passing between sources and destination..
after getting parsed ,it should print reponses from the destination
for eg-
if A,1,B is first line then,
B,1_1,A
should immediately follow after the first line,
and hence there is some logic in getting the output
it is something like, B is sending some response ACK for the message 1 to A

and same follows to other inputs..
input file
A,1,B A,2,B A,1,C C,1_1,A B,2,D B,1_1,A B,2_2,A B,2_2,Dafter parsing
A,1,B B,1_1,A
A,1,C C,1_1,A
A,2,B B,2_2,A B,2,D D,2_2,Dthis is the required output:-):slight_smile:

thanks and regards
raghuraipur

4

OK... I think I'm starting to understand. You just need to reshuffle the lines so that the A-msg-B is followed by B-msg_msg-A.

Try this. Not super efficient, but should work:

IFS=',' 
while read src msg dst ; do 
  [[ $msg =~ _ ]] && continue 
  echo $src,$msg,$dst 
  grep "${dst},${msg}_${msg},${src}" responses.txt
done < responses.txt

where responses.txt is your input file

5

hi mirni,

thanks for that,
but my task is being assigned to be deal with perl, scripting..
could you help oout for the same..

thanks in advance
raghuraipur