Date: Mon, 3 Jun 1996 16:29:21 +0100 (BST)
From: Rich Deighton <rad AT lucel DOT demon DOT co DOT uk>
To: djgpp AT delorie DOT com
Subject: Re: I/O Multiplexor
In-Reply-To: <Pine.SUN.3.91.960603131243.21344B-100000@is>
Message-ID: <Pine.LNX.3.91.960603161851.427A-100000@lucel.demon.co.uk>
MIME-Version: 1.0
Content-Type: TEXT/PLAIN; charset=US-ASCII

On Mon, 3 Jun 1996, Eli Zaretskii wrote:

> 
> On Sat, 1 Jun 1996, Orlando Andico wrote:
> 
> > Forgive my ignorance, but what's the use of having select () on a single 
> > threaded file system? (of course, this is not mentioning the nonexistent 
> > sockets library.. ;)
> 
> I can think of a few uses:
> 
> 	1) Portability.  How else would you write a program that polls 
> the keyboard in a way that would run on both MS-DOS and Unix?
> 
> 	2) An infrastructure for implementing file-system extensions, like
> the sockets. 
> 
> Anyway, this thread was started when somebody asked what should they use 
> instead of `select', probably because they don't know DJGPP *has* 
> `select'.  They didn't tell why did they need it.
> 

I must apologise for failing to grep for select() in the djgpp header files.
However, I was a little heart broken to see that the tcp library for djgpp
seems to handle sockets in an nonconvenient way. I realise that it's only
version 0.11 or some such thing, but there are some vast problems in using
it for anything useful. 

I was looking for select() so that I could, at regular intervals, poll a set
of file descriptors for input. The tcp library not only re-defines fd_set,
select, etc but also doesn't use "valid" file descriptors. Therefore you can't
use one select call for a set of fd's containing sockets as well as stdio 
handles. This makes things a tad messy.

Are there any other TCP/IP implementations that could be compiled up under 
DJGPP? I have a great need for TCP/IP in a bunch of client/server stuff I'm
working on under Linux and porting, with DJGPP to DOS. 
I've got too use to the GNU C extensions to use a commercial C compiler.

Any help would be appreciated.

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