[ethereal-users] Need some advice and help getting started with real time packet monitoring

["Nathan Good" <goodx013@xxxxxxxxxx>]

Hello. I am working on a project that involves monitoring certain UDP
packets, and then responding to those in real time based on the data within
them. I came across ethereal and libcap, but it looks like all the packet
data is buffered and then analyzed. Realizing that I need help from the
experts, I turn to you for advice.

Here is what I have and what I want to do:
Have:
Linux box (Caldera 2.3 Open Linux)

What I want to do:
look at all UDP packets coming across wire in real time ( To be run all the
time)
If packet data contains such and such, capture this data to a C struct or
something, and pass it to my client program for processing.

Thats pretty much it. i am not sure if ethereal is the tool for this or if
libcap is. If I am completely looking in the wrong direction, please let me
know so. I am very new to packet stuff, so sample source or pointers to such
would be very much appreciated.

Thank you very much for your help,

NSG