Parsing j1939 from raw candump

[Giox79 <giovanniparodi79@gmail.com>]

Hello everybody, I would like to ask some suggestion.
As said in a previous post, I rebuilt candump utils on a 
custom board with a can interface.
I've been able to capture data using the 
canlogserver  util and everything worked fine. 
Now I would like to build a SW application, 
running in a PC and receiving the data from canlogserver. 
This application should parse raw candump packet and 
extract j1939 packet.
Is there anyone that can suggest me how to approach 
this topic? I tried using the j1939-71 standard, 
but as far as I understand, it explains differences between 
different packages, but I didn't find an 
explanation about header and trailer of J1939 packet.
Please note that I have the whole j1939 standard and that 
at present time I can't integrate the j1939 canutils in linux 
kernel because I should use for other kind of constraints 
a 2.6 linux kernel.
Any help, reference to specific sections of j1939 standard
 and so on will be appreciated.
Giovanni