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Michael_Koyfma1's avatar
Michael_Koyfma1
Icon for Cirrus rankCirrus
Nov 03, 2006

Payload manipulation question

Basically, once I have the payload, I need to identify a piece that starts with FO followed by 5 digits, then three spaces, and then B. I need the send back the payload back to the client, only I nee...
application delivery
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Deb_Allen_18's avatar
Deb_Allen_18
Historic F5 Account
Nov 04, 2006
Hi Michael -

 

 

Looks like you're OK with using a wildcard to identify the 8 characters between "FO" & "B", so following your approach, you would actually want to break up the match string into /4/ chunks, and only replace the whitespace, using regsub instead of regexp to perform the inline substitution. This code would do the trick:

 


   set payload [TCP::payload]
   set new_digits ""
   regsub -all "(FO)(.*)(   )(B)" $payload "\\1\\2$new_digits\\4" payload
   TCP::payload replace 0 [TCP::payload length] $payload

 

 

HTH

 

/deb