do_tcp_sendmsg

This function is the workhorse of the TCP/IP suite in Linux. This is the function that actually sends out an information packet.

The first check that this function does is to see if the connection is established. For T/TCP we don't need to be established as we are using an implied open-close model.

The state processing for T/TCP follows the pseudo code shown below, the code can be seen in appendix A.2.1:

timinput{code/pseudo_sendmsg}}{\scriptsize \pr

Once the pre-processing for the segment is complete, the CC options needed are calculated and then added onto the segment. See appendices A.1.1 and A.1.2 for this code.