UNIX-to-PC communications help needed

[Tillman Basien]

gordon at osiris.cso.uiuc.edu (John Gordon) writes:

>I write:

>>	Hi, Netters.  I'm going to be working on a project that involves
>>a PC dialing up a UNIX system, getting some information, and then logging
>>off and processing the info.  The information could be small (< 5K) or
>>large (> 2-5M).  Does any one have any suggestions on how to do this?
>>Or any source code that would have helpful examples?  Any info will be
>>greatly appreciated.

>	Upon further thought, I think that I should have stated my
>needs a little clearer.  What I need is for the user to enter a search command
>into the PC, then the PC calls up the Unix system and relays the search
>command to a database, then captures the resultant information and sends
>it back down to the PC.  I am not sure exactly how is the best way to do
>this: have the Unix end save the info to a big file and just download it
>to the PC, or maintain the connection and just send info record-by-record
>as the user requests it, or what.  Something I would really be interested
>in would be C source examples of PC-Unix communications via a modem.
>Sorry that I did not make myself really clear on what I wanted.  If anyone
>could provide more help, I would be grateful.

Ok, Well this is an interesting question and I want to bring my idea up to
it.
So you want to dial, so it will be over telefon. Ok
If you use procomm or in germany we have a equel product called telix you
can setup chat-script to dial to conect to start host jobs and to download
via a protokoll (x-Modem, Kermit waht you want). 
There is still a nother product ICE.TEN.PLUS which can tranfer files, and
has the best terminal emulation.

If you have big files to transmit, so you must think wether it is
neccessery to transmit all if it. We have a customer with a fine
application to download supply information from hist UNIX host to local
dailing in PC. The PC is sending a inital request to the host, and the host
transmit only that kind of information which changed since the last
request. For example only the telfon nummber of customer xyz with nummer
1234, the host transmit something like 1234,t,<new nummer>.
This will minimice your traffic.

To realize that kind of application you can use Greenleaf Communikation
Library. This is a very good toolbox for DOS to setup the COM-ports. It
includes the hole C-Source code, x-modem protokolls and all what you need.
In the UNIX box you must write your own toolbox, but for the protokolls you
can port parts of greenleaf or you use someting for PD.

If there are further questions, feel free to email

Tillmann

-- 
					             basien at PEM-Stuttgart.de
Dipl.-Ing. Tillmann A. Basien           PEM Programmentwicklungsgesellschaft
Vaihinger Str.49, PostBox 810165                      fuer Microcomputer mbH
FRG 7000 Stuttgart 80             voice: +49-711-713045  fax: +49-711-713047