Text-based Web Browsers for the PC

[n.mueller_bEi_hit.handshake.de (Norbert Mueller)]

## Nachricht vom 02.06.97 weitergeleitet
## Ursprung : n.mueller_bEi_hit-n.mueller.zer
## Ersteller: BERNHARD_bEi_mvblind.uni-linz.ac.at
 
Dear folks,
since many people have asked me about this topic and since I myself
find it highly interesting, I have been going into an intensive
testing program of all texb-based Web browsers available for the PC.
Since the first test results sound very, very encouraging, it is my
intention to continually inform you about the progress of my work. I
am happy if my comments are of some help for you, but, if you wish to
be removed from this mailing list, please let me know.
 
This first article describes some portations of the famous text
browser Lynx to the PC. Subsequent articles shall describe browsers
such as NetTamer or WebLos.
 
To begin with, a brief remark of a more personal nature: When Norbert
Mueller pointed me to Bobcat, a small version of Lynx under DOS, I
ignored the posting for about two months. Why that? Well, my
experiences with the program DosLynx, a tremendously bad version of
Lynx for DOS with an interface horrible for the blind, made me think
that I would waste my precios time when playing with a new
application of this kind. When finally inspecting Bobcat some weeks
ago I found that I made a blatant mistake, because the program offers
much benefit for its size and for the limitations under which its
author had to develop it. However, the even better news is that my
final readiness to give Bobcat a chance was highly rewarded by the
upcoming "real" Lynx portations which now appeared on the market.
 
In fact, there are now two portations of Lynx, one for the Windows
operating system and one for DOS, which encompass all the features of
Lynx with a few restrictions; moreover, the developers assure that
these portations shall keep track with the Lynx development for UNIX
and VMS, the native platforms for this excellent browser.
 
Now, Let's finish the gossip; here are the facts:
 
About LYNX_386: This runs on a 386 or greater, which means, de
facto, it runs on every modern PC. In order to overcome the fateful
DOS restriction of 640 MB of RAM, the program needs a DPMI driver. A
packet driver is needed to connect to the Internet.
 
 
DPMI driver, then edit the file WATTCP.CFG - this is the
configuration file for the integrated Waterloo TCP stack. Finally,
you might customize the LYNX.CFG file, as well known from the UNIX or
VMS original.
 
As for the DPMI driver, one is supplied in the FTP directory
mentioned at the end of this report. This driver, called CWSDPMI, is
very easily installed: Simply unzip the archive with the command
 
pkunzip -d csdpmi3b.zip,
 
then go to the directory BIN created by the unzipper, and start the
driver with the command
 
cwsdpmi.exe -p
 
that's all about it. For this driver to work, no other memory
manager, not even HIMEM.SYS, has to be installed. Do not forget to
unload the driver when you do no longer need it, because it occupies
almost 50 K of conventional or upper memory: This is done with the
command
 
cwsdpmi.exe -u
 
Restrictions and problems: Presently, FTP and NetNews do not work
with LYNX_386. Also, the z command to cancel a network transfer seems
to be of no effect.
 
About LYNX_W32: This runs on a Windows system, however, only on a
true 32-bit version of Windows, i.e., Windows 95 or Windows NT - no
support for windows 3.11 or lower, even if the WIN32S package is
applied. The installation of this program is even simpler than that
of the DOS counterpart: Simply make the necessary modifications to
your LYNX.CFG file, then start the program. Of course, in order to be
able to browse non-local pages with the program, Windows 95 or
Windows NT needs to be configured for TCP/IP.
 
Restrictions and problems: Presently, there seems to be a problem
with international keyboard support: When, for exapmle, the German
keyboard driver is loaded, then the latin letters are located at
their normal positions, but most of the special characters such as
slash, semicolon etc. cannot be written with their usual keys - the
keyboard mapping is a very strange one. Moreover, as mentioned for
the DOS version, the z command to cancel a transfer seems to be
inoperative.
 
Mouse support: The Windows portation of Lynx supports the mouse to
some extent: When you position the mouse pointer over a hyperlink,
you can follow this link by double-clicking the mouse - heaven knows
why they chose double instead of single clicks for this.
 
LYNX_W32 and DOS boxes: The Windows portation works by opening a DOS
box when active, closing it when oyu exit the program - it is one of
the very few Windows applications known to me which cannot be exited
by the famous ALT-F4 keystroke. This behaviour has as a consequence
that in some sitations where the Lynx screen is transitory you cannot
watch it on the Braille display: The DOS box closes, and there is no
trace of the screen left. For example, such a situation would happen
when oyu start the program with the command
 
lynx -version
 
in which case the program is envoked, shows a version screen, and
exits immediately. To overcome such a sitation, apply a simple trick:
Open a DOS box prior to starting LYNX, and start the program from
the DOS prompt of that box: This wastes a small amount of memory, but
you can be sure to see everything that happens on your Braille
display.
 
Some general hints about both portations: Both programs presently
seem to have difficulty storing the .lynxrc file and the bookmark
file in reasonable places: Whereas in a UNIX implementation these
files are stored in the current user's home directory, the concept of
a home directory as well as that of the current user are meaningless
on a DOS or Windows machine. In order to have a place for the files,
the programs interrogate the environment variable TEMP, storing the
files to the path pointed to by that variable. You should therefore
surround the program by a batch file that maintains reasonable
storage of these important files. Of course, the file .lynxrc cannot
be stored by this name: Rather, it is called LYNX.RC in these
portations in order to comply with the DOS naming conventions.
 
How to get the software: It is fairly easy to download the programs
discussed here from the URL
 
lynx.browser.org
 
Howerver, to make thins even easier for you, I have stored the
programs on my FTP server, which has the address
 
fbi.mvblind.uni-linz.ac.at
 
Here, there is an account with the name browser and with the password
pcbrowser. (Please do not include the period or full stop in the
password). Thus connecting to my file server, you can download the
portations together with the above mentioned DPMI driver. For
reasons of comparison, but also in honour of the BOBCAT pioneer whose
work has lost most of its value by now, you can also find a copy of
the latest BOBCAT release there. Finally, this directory will always
contain copies of the files posted to you about PC text browsers,
beginning with this file, info1.txt, numberd in increasing order.
 
 
Educational Endeavor "Computer Science for the Blind",
University of Linz, Department for Computer Science,
Altenbergerstrasse 69, 4040 Linz, Austria.
Bernhard Stoeger               Tel.: +43/732/2468/9232, Fax: -/9322,
email: bernhard_bEi_mvblind.uni-linz.ac.at
    "I can't see my computer, my computer doesn't watch me, but
     together we conquer the world." (not Shakespeare!)