tcp_poll? What is that?

[Andy <andy@xxxxxx>]

Hello!

I am working on a new transport layer protocol and am using TCP as an
example.
Here is my problem. I found function tcp_poll (Linux 2.4 - pre3 test3:
net/ipv4/tcp.c:554).

The description says:

547 /*
548  *      Wait for a TCP event.
549  *
550  *      Note that we don't need to lock the socket, as the upper
poll layers
551  *      take care of normal races (between the test and the event)
and we don't
552  *      go look at any of the socket buffers directly.
553  */

Can anybody explain if this is used and what is the condition when this
is used?

                        Andy