Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!psuvax1!ukma!xanth!mcnc!decvax!virgin!zinn!pulsar!gmd
From: gmd@pulsar.UUCP (George MacDonald)
Newsgroups: comp.sys.amiga
Subject: Porting DNET to SYS V & Amiga uucp/news
Message-ID: <1193.AA1193@pulsar>
Date: 11 Aug 89 04:06:49 GMT
Followup-To: comp.sys.amiga
Lines: 54


 Re: DNET for SYS V

In article <907@corpane.UUCP> sparks@corpane.UUCP (John Sparks) writes:

   Many Amiga/Unix users will appreciate it if DNET on SYS V is possible.
   Does it/ will it exist?

DNET utilizes the socket functions first provided in the Berkeley 4.2 
distribution of unix. These C language functions have been ported by a 
number of vendors to their system V based platforms. This is usually done 
when a vendor is interested in providing networking capabilities(TCP/IP, 
NFS ...). The system V branch of unix lacked good support for networking
and remote file sharing until SV.3 when support was added for streams and 
RFS(remote file sharing). 
The programmers library providing for this is called TLI(Transport Layer 
Interface), and is very similar to the socket function calls. In fact it is 
almost identical, so a port to Sys5.3 or greater looks to be relatively 
straight forward. Of course Sys 5.4(Out to developers now) will provide 
both sets of functions so it then becomes a moot point.

Porting DNET to anything before 5.3 without the socket library will be
a chore. The major problem in emulating the socket functions will be 
providing multiplexed input on a single channel(serial line). This needs
to be done in the kernel to do it properly, hence a device driver is needed.
I am not familiar with DNET internals, and not sure which address domain it 
uses (UDP, INET ...) or which socket communication style(stream or datagram).
If DNET uses UDP and stream sockets then emulation using named pipes seems
at least possible. If DNET uses INET it will be more difficult and
the device driver will be required. The AT&T Blit(a programmable graphics
terminal) used a device driver approach to solving this problem in Sys 5.2, 
the driver was called mpx, see the BLTJ Oct 84 for more details on this.

I guess the bad news is that it is unlikely you will see DNET on Sys 5.2,
although I agree it would be nice. On the other hand DNET should crop
up on Sys 5.3 and 5.4 without too much effort. 

It would be a fun project, Ahh if only I didn't have to sleep!! 8-)


p.s.

This article was composed on my 2500 running AmigaUUCP .50, are their
many other users of this sofware out there? I have been using this
package to receive mail and news for several months now. My only problem
with it is the newsgroups fill up to quickly!! Is anyone working on 
an upgrade to the software?


--
      /\  George MacDonald, Pulsar Software Inc. - Unix Software Consultants
_____/  \    _____  ..{harvard,decvax}!zinn!pulsar!gmd or gmd@pulsar.mv.com
         \  /       
          \/   36 Hickory Ln,  Windham, N.H.  03087  Tel (603)-434-2614