			THINGS TO IMPLEMENT
			------------------

	Before you can get anywhere with MSN, you must implement a certain 
subset of the functions. Everything else may be left as "dummy" functions 
for now, but you MUST implement the following:

(1)	int ext_connect_socket(char * server, char * port)

	This code should make a TCP connection to the specified server and 
port, and return a UNIX file descriptor for that connection, or -1 on 
error.

(2)	void ext_register_sock(int fd)

	"fd" is a UNIX file descriptor. This function must set whatever 
poling function is in place to call msn_handle_incoming()  whenever there 
is incoming data on that socket.

(3)	void ext_unregister_sock(int fd)

	This socket has been closed and is now of no more interest for 
polling purposes. Remove it from whatever internal list you are 
maintaining.

(4)	Polling loop

	When control is outside the MSN library (ie in your program), you 
must periodically check for incoming data on any of the sockets the 
library has registered interest in (with ext_register_sock()), and call 
void msn_handle_incoming(int fd) when traffic is received on any file 
descriptor. (The parameter "fd" should be the file descriptor with 
incoming traffic). If any socket has closed, the function
void msn_handle_close(int fd) should be called with the appropriate file 
descriptor. This will result in a call to ext_unregister_sock for that 
file descriptor, and a tidy cleanup.






	If you want a "quick start": For everything else, you can just 
look in  msn_interface.h, and implement appropriate dummy functions.
