Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!cs.utexas.edu!uunet!microsoft!bradch
From: bradch@microsoft.UUCP (Bradford Christian ms1)
Newsgroups: comp.sys.amiga.tech
Subject: Re: I wanna have a DOSGate!
Keywords: Citadel, DOSGate, door, bbs
Message-ID: <6043@microsoft.UUCP>
Date: 15 Jun 89 22:45:56 GMT
References: <16317@gryphon.COM> <5866@microsoft.UUCP> <682@madnix.UUCP> <6013@microsoft.UUCP> <17575@louie.udel.EDU>
Reply-To: bradch@microsoft.UUCP (Bradford Christian ms1)
Distribution: na
Organization: Microsoft Corp., Redmond WA
Lines: 31

In article <17575@louie.udel.EDU> new@udel.EDU (Darren New) writes:
> [...] In my BBS I plan to go multi-user by having multiple
>copies of the BBS running at once, possibly after writing the
>code to be residentable (seemed obvious to me :-).  [...]

I don't know if you've thought about this yet or not so I thought I'd
bring it up: multiple instances do not a multi-user program make.  If
your program has any sort of data-base (like messages, mail, etc.), then
you will have to coordinate access to the data base.  For example, if
your message base is one big file (a good thing to do to avoid wasted
bytes at the end of blocks), then one user reading the file will prevent
another user from adding a message to it.  Running totaly separate
instances will probably also make a CB mode (where two users can chat
with each other directly) difficult.

My solution to this problem is to have one instance of the program handle
any number of users.  The main process manages the data base and is the
only thing that has access to these files.  Each port has it's own process
which sends messages to the main process when it needs to read or write
an item in the data base.  This solution not only solves the data base
access problem, but also makes it real easy to allow two (or more) users
to chat.

I hope this doesn't mess up your plans, but if you hadn't thought of this
and haven't started coding yet, it should be worth thinking about.  A
possible alternative to the method I use would be to write a multi-user
data base handler as a separate program.  You could then run multiple
instances of you BBS program, one for each user, which would access the
data base by sending messages to the handler.

Good luck with your program!