[comp.unix.xenix.sco] Connect Speed

bbs@alchemy.UUCP (BBS Administration) (04/29/91)

Here's the situation:

PC Clone running SCO Xenix v2.3.2 with a Telebit T2500 attached to a "dumb"
serial card and a fixed data rate between computer and modem set to 19,200
bps.

Here's the problem:

The BBS program we're writing always reports the connect speed to be this
speed (19,200 bps) when appending a caller log file. We need to fix this
speed so that if a user calls in using some kind of compression protocol
we can take advantage of it by sending data to the modem faster than the
connect speed between modems, but at the same time, we'd like to know
what the >actual< speed is between the modems.

Our current method of determining the connect speed is to do an ioctl ()
on the tty and examine the c_cflag element of the termio structure. This
worked in the past when we didn't fix the "baudrate", but no longer works
as we'd like.

Is there a solution that allows the computer<->modem speed to remain locked
at 19,200 but still permits our program to obtain the actual >connect<
speed between our modem and the callers' modem? The solution must be
hardware independent so examining some register of the modem is not a
viable alternative (unless there is some industry standard that places
this information in a consistent location; and even then, "peeking" this
out of the modem would be a project in and of itself).

Please email any suggestion you might have and if there is sufficient
interest in my findings, I'll post a summary. Thanks in advance!

-- John

John Donahue, Senior Partner | UUCP: ucrmath!alchemy!{bbs, gumby} | The Future
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larry@nstar.rn.com (Larry Snyder) (04/29/91)

bbs@alchemy.UUCP (BBS Administration) writes:

>Here's the problem:

>The BBS program we're writing always reports the connect speed to be this
>speed (19,200 bps) when appending a caller log file. We need to fix this
>speed so that if a user calls in using some kind of compression protocol
>we can take advantage of it by sending data to the modem faster than the
>connect speed between modems, but at the same time, we'd like to know
>what the >actual< speed is between the modems.

why not modify (or replace) getty to accept the return rate from
the modem (ie: CONNECT FAST, CONNECT 2400, etc.) and pass that to
the BBS - while keeping the DTE locked at 19200?

We have such a getty here on nstar in our archives..

-- 
      Larry Snyder, NSTAR Public Access Unix 219-289-0287/317-251-7391
                         HST/PEP/V.32/v.32bis/v.42bis 
                        regional UUCP mapping coordinator 
               {larry@nstar.rn.com, ..!uunet!nstar.rn.com!larry}

rahim@cse.uta.edu (Khalid Rahim) (05/03/91)

I have question for UNIX programmers !!
I am working on developing a YACC specifications,
and I am not sure how to invoke a file from the
YACC code.  I want to open up a file and should
be able to read it from YACC code.
If any of you have done it before or worked exclusively
with YACC before, please do let me know the secret !!!!
Thank you very much

Emain to:

rahim@evax.uta.edu

srodawa@vela.acs.oakland.edu (Ron Srodawa) (05/03/91)

In article <1991May2.233629.25541@cse.uta.edu> rahim@cse.uta.edu (Khalid Rahim) writes:
>YACC code.  I want to open up a file and should
>be able to read it from YACC code.

YACC code normally reads from standard input.  It calls a routine named
yylex to read each token.  If you wrote your own, then the solution
would be obvious.  I assume you used lex to generate this.  List the
entries in the library gotten by -ll (the lex library).  One of these
will obviously be the read routine.  Write your own with the same name.
Now that can open your file.

BTW, the source code for the -ll and -ly routines is quite trivial.
Some of it is given in the lex and yacc documentation verbatim.  You
can also look at the lex documentation for a description of how lex
reads characters.

As a university, we have a source code license for Unix so we just modify
the library code (a copy of it) when we need to do this.  You might look
to flex and bison for freely available equivalent code.

-- 
| Ronald J. Srodawa               | Internet: srodawa@vela.oakland.edu      |
| School of Engineering and CS    | UUCP:     srodawa@vela.UUCP             |
| Oakland University              | Voice:    (313) 370-2247                |
| Rochester, Michigan  48309-4401 |                                         |

martin@mwtech.UUCP (Martin Weitzel) (05/04/91)

In article <1991May2.233629.25541@cse.uta.edu> rahim@cse.uta.edu (Khalid Rahim) writes:
>I have question for UNIX programmers !!
>I am working on developing a YACC specifications,
>and I am not sure how to invoke a file from the
>YACC code.  I want to open up a file and should
>be able to read it from YACC code.

I posted a long article which answered this and some more lex/yacc
related questions around July 1990 to comp.unix.wizards. Sorry, but I
have no other pointers than the subject - it was

	"Re: yacc & lex - cupla questions"

I could repost a slightly revised version of this article, but I'm not
sure if there's sufficient interrest.

(To Khalid: If no kind soul mailed you my article and there's no way to
get it from a local site that is archiving c.u.w, drop me a note.)
-- 
Martin Weitzel, email: martin@mwtech.UUCP, voice: 49-(0)6151-6 56 83