From: Richard Dawe <rich AT tudor21 DOT net>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: networking and DJGPP...
Date: Fri, 04 Feb 2000 19:57:53 +0000
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To: djgpp AT delorie DOT com
DJ-Gateway: from newsgroup comp.os.msdos.djgpp
Reply-To: djgpp AT delorie DOT com

Hello.

> For network (TCP/IP or IPX) I know that I have to a library called
> TCP-Lib (or something to that effect)

Take a look at libsocket:

http://libsocket.tsx.org/

or Watt-32:

http://www.bgnett.no/~giva/

libsocket works with Windows. Watt-32 works with DOS. I'm currently trying
to merge Watt-32's code into libsocket, so that libsocket will run on DOS
& Windows.

> and for Modem there is something called Serial-something.

bcserio? dz-something or other? I can't remember off the top of my head.
Take a look in v2tk/ of the DJGPP archive. I know nothing about serial
communications.

> Lets say I want to write a small program that passes 3 items
> to the other computer: angle, velocity, and the userid...  how would I
> write this???

You need some kind of communications protocol. You could just send
structures like:

struct data_item {
	float angle;
	float velocity;
	uid_t user;
};

If this is running on multiple platforms (i.e. more than just DOS,
Windows), then you might have to think about how the data is sent - big
endian, little endian, etc.

With the networking you have a choice of protocol - TCP over IP or UDP
over IP. If you use TCP/IP, then it's possible that the whole of the above
structure would not be sent in one packet. You may like to use UDP/IP
instead. I recommend reading some books on TCP/IP networking programming,
like W. Richard Stevens book on Unix Network Programming (very good book).

We had a discussion on the libsocket mailing list a while back about using
networking in a game. It may be worth looking at the libsocket mailing
list archives - look at the mailing list page here:

http://libsocket.tsx.org/

> If there is a web-site about this, plz direct me to it...

For BSD sockets networking, which both libsocket and Watt-32 support, take
a look at Beej's guide:

http://www.phekda.freeserve.co.uk/richdawe/lsck/beej/

HTH, bye,

-- 
Richard Dawe
richdawe AT bigfoot DOT com ICQ 47595498 http://www.bigfoot.com/~richdawe/