[Winpcap-users] About TCP/UDP/ICMP checksum

[ZhiyuHe]

I'm writing a simple protocol analyzer for my graduation project using
WinPcap.This mailing list and Guy Harris has given me too much
help,thanks very much.
I should calculate the TCP/UDP checksum in my program,but it's so
difficult for me.I have perused <<TCP/IP Illustracted Volume 1>>
(Richard Stevens) and RFC1071,and have searched this topic in
Google,WinPcap mailing list archive,and ethereal.com,but I still can't
manage this.I don't understand how to process TCP/UDP psuedo
header,and how to calculate.I need a demonstration.
Thanks a lot!