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Next: Functions for Window Up: 28.4 Architecture and Internals Previous: The TCP header Functions for Sending Data

Note that generally the sending TCP never actually sends data (it only sets the packet size).

send_much(force, reason, maxburst) - this function attempts to send as many packets as the current sent window allows. It also keeps track of how many packets it has sent, and limits to the total to maxburst.
The function output(seqno, reason) sends one packet with the given sequence number and updates the maximum sent sequence number variable (maxseq_) to hold the given sequence number if it is the greatest sent so far. This function also assigns the various fields in the TCP header (sequence number, timestamp, reason for transmission). This function also sets a retransmission timer if one is not already pending.