IntraDOS 1.2
Intranet HTML Browser for DOS

IntraDOS is an HTML browser for DOS-based PCs, mainly for office intranets and other hypertext needs. It is not a web browser, but it attempts to duplicate many features of popular web browsers for documents that are written in HTML and available on a PC's hard drive or network, while using less than 280K of RAM. I created it so that DOS 386 machines in my office could share the same intranet resources with the Windows Pentiums quickly and easily and so that I did not need to implement two sets of hypertext documents. To activate one of these links, click on it with a mouse or press TAB to select one and ENTER to activate it:

Key Features of IntraDOS
Recommended System
Setting up IntraDOS on a network
Launching IntraDOS
Navigating the Intranet
Selecting Options
Included Files
Known Limitations
Improvements over IntraDOS 1.1
How to Register
Redistribution Limitations

KEY FEATURES:

DOS-file system support.
Unlike other DOS-based HTML browsers, IntraDOS recognizes the DOS file structure (e.g., c:\htm\file.htm) as well as the internet standard (e.g., file:///c:\htm\file.htm). This will be easier for intranet administrators to code.
Imitation of Leading Windows Browers.
IntraDOS attempts to mimic the operations of leading Windows web browsers to the extent that a text-based program can do so. Back, Ahead, and Home menu options function like the buttons on popular browsers. Standard Windows keystrokes apply (Home, End, Ctrl+Home, Ctrl+End), and scrollbars can be used as in Windows. Search for text with Ctrl+F, and repeat the search with F3.
Keystroke support.
IntraDOS allows the mouseless user (and those of us who continue to think that the keyboard is faster) to select links without a mouse by using the TAB key (or Shift+TAB to go in the reverse direction). Menu items (e.g., the Back button) are activated by pressing Alt+ an accelerator key (e.g., Alt+B to go back).
Color coding of HTML tags.
Bold, italic, and H1 to H6 tags are color coded, as are links. Users can now set their preferences as to how those colors will be displayed.
Tables support.
Unlike any other DOS browser I've seen, IntraDOS supports basic tables (but not tables within tables) in text mode. (I've seen only one other DOS program that supports tables in graphics mode, but it was too slow rendering the tables on old PCs.)
Jumping to Name Anchors.
Unlike other DOS browsers, IntraDOS fully supports jumping to name anchors (e.g, c:\htm\index.htm#nameanchor), even if the anchor is in a file other than the current one.
Stockpile of Pre-parsed Files.
Because IntraDOS attempts to implement many formatting codes, parsing large HTML files can be slow on a 386 machine. Therefore, IntraDOS gives the user an option to save the parsed file in a stockpile (formerly called a registry) so that the same file does not need to be parsed again (unless it is updated, which IntraDOS checks automatically). A 386 machine reading a long pre-parsed file from the stockpile can display it about as quickly as a Windows browser on a Pentium can parse it and display it. (See statistics below.)
By default, IntraDOS does not save files in the stockpile, though the user can set the program to save the files automatically or to force the user to make a decision about saving each file. The user can also save files in the stockpile at-will.

My philosophy: The DOS machines may be dinosaurs, but they should still not die prematurely. Don't junk them just to give all your users access to an Intranet.

Recommended System:

IntraDOS has been extensively tested on my office's 386 machines running MS-DOS 5.0 with VGA monitors. Anything better is great. I haven't tested the program on other monitors, on slower processors, or earlier versions of DOS. If you experience problems with those systems, please feel free to let me know, though I cannot guarantee that I can help.

Here are some performance statistics for our office intranet. Your mileage may vary. Times are in seconds. Using IntraDOS, the first number is the time it took to parse and show the file; the second is the time it took to read a pre-parsed file from the registry. (2 386 PCs were used, hence the variation.) Using MSIE, the first number is the time it took to link to the file; the second is the time it took using the back/forward buttons.

Files Bytes IntraDOS
386
16MHz
IntraDOS
Pentium
75MHz
MSIE
Pentium
75MHz
Startup File
(Program
startup time
included)
2,713 5-6 -- 3 <2 -- <1 4-11 -- NA
File 1
5,995 4-6 -- 1-2 1 -- <1 2 -- <1
File 2
12,645 7-10 -- 1-2 1.5 -- <1 2+ -- <1
File 3
17,093 9-14 -- 1-2 2 -- <1 2.5 -- <1
File 4
32,144 18-24 -- 2-3 <3 -- <1 <3 -- <1
File 5
50,276 25-36 -- 2-3 <4 -- <1 3 -- <1

These statistics show the improvement that pre-parsing files can make. I do not recommend having 386 users wait to parse a file requiring more than a few seconds to parse.

Recommended preliminaries on a network:

  1. Place the program file IntraDOS.EXE in a directory on your network server (e.g., X:\INTRADOS) accessible to those with DOS machines who will use it. This directory will store:
    (a) The online help file (ID-Help.htm).
    (b) The registration information file (IDReg.cfg) when the program is registered.
    (c) Individual user setup files recording color and other selections (ID-abc.cfg).
    NOTE 1: Thus users need to have creation and deletion rights in the directory.
    NOTE 2: The help file can be changed by the menu under File, Setup, Help File.

  2. Prepare one or more appropriate start-up files (home pages) for network users. Since this program allows the network administrator to call any file as a start-up file, he/she can set the browser to start with a file that may be appropriate to different contexts in the office setting.

  3. Put your (users') startup HTML file(s) in a public directory. This directory can be, but need not be, the same as the directory containing the program files. This directory will store certain files generated by IntraDOS:
    1. Temporary files as users parse HTML files on the intranet of the form $abc.1 (2,3,4, etc.). These are deleted by normal program termination.
    2. A database file listing files in the permanent stockpile known as IDPF.lst.
    3. Preparsed files that are stockpiled, in the form IDPF.1 (2,3,4, etc.)
    NOTE 1: Because IntraDOS places temporary files in this directory, users need to have read, write, create, and delete rights in this directory. If the network administrator wishes to give read-only access to certain files, those should be placed in a separate directory where users have limited rights.
    NOTE 2: The location of temporary files can be changed by the menu under File, Setup, Location of Temporary Files.

  4. If not already done, each user should have his/her environmental variable USER set to three letters (initials). To avoid conflicts, the initials should be unique. Most machines on a network have this variable set at the time of logging in to the network.

  5. The administrator should preview all the files on the intranet with IntraDOS on a fast machine and save at least the large ones (if not all files) in the permanent stockpile, so that users on slow machines can view the files quickly.

Launching the program:

You can start IntraDOS by the command line or by a batch file. IntraDOS will open a startup HTML file as follows:

Here are some sample batch files for launching IntraDOS:

1. Where the network has set the user variable, the startup file is called Home.HTM and is located in the same directory with IntraDOS.EXE:
x:
cd\Intrados
IntraDOS

2. Same, but the startup file is located elsewhere:
x:
cd\Intrados
IntraDOS x:\public\html\startup.htm

3. Where the user needs to start in the HTML directory and IntraDOS is in the user's PATH.
x:
cd\public\html

IntraDOS startup.htm

4. Same, but IntraDOS is not in the user's path.
x:
cd\public\html
x:\intrados\IntraDOS startup.htm

5. Same a #3, but the USER variable has not been set by the network software:
SET USER=ABC
x:
cd\public\html
IntraDOS startup.htm
SET USER=

Navigating/Exploring via Hypertext Links:

As with other browsers, a user can move through the information system by activating links. In IntraDOS, the links appear in yellow. A link does not change color after a user has activated a link.

Like popular Windows-based browsers, a user may follow hypertext links by clicking on them with a mouse or (more laboriously) typing the target file name.

Unlike the Windows-based browsers, IntraDOS allows a user to follow a link without a mouse by means of the TAB key. To select a link, press TAB until the desired link is highlighted (or Shift+TAB to cycle through the links in the reverse direction). Then, the user presses ENTER to activate the link. If you scroll so that the active link is out of view, IntraDOS interprets a TAB as calling for the first link on the screen rather than the next link in order.

Selecting Options:

Screen Colors.
Users may set default color preferences by clicking the menu under "File, Setup, Colors." The currently selected colors are shown. The user can experiment with the color scheme by clicking the menu item "Change," selecting a screen display item to change, and scrolling up and down the color list box until a suitable color scheme is selected for each item.

The user can save the color changes by clicking the "Save" button and exiting, or disregard the changes by exiting without saving.

Stockpile of Pre-parsed Files.
This option, which will be of importance mainly to the intranet administrator, allows the automatic saving of pre-parsed files to a "stockpile," a permanent cache, which improves performance on the intranet, particularly for slower PCs.

By default, no files are automatically saved to the stockpile. The user may add files to the stockpile only by clicking the "File, Stockpile Permanently" option (Ctrl+P).

The user can change the default by clicking on "File, Setup" and selecting whether to save all automatically, or to force the user to decide on each file.

If you create more than one start-up home pages on different directories, stockpiled files will be left in the different directories. This will not be a problem if there is little overlap between the two sets of files, but if there is a significant overlap, it would be better to keep all start-up home pages in the same directory.

Included Files:

Known Limitations:

As with any other browser, with sufficient ingenuity (or sufficient sloppiness) one can write a page in HTML that will confound IntraDOS. In testing this on many, many files drawn from the internet, I've found huge numbers of badly written HTML files. I have attempted to do a lot of error trapping in IntraDOS, but it is impossible to catch them all. This browser should be able to represent any moderately well-formulated ordinary page of HTML, but I cannot guarantee that all pages can be parsed or that, if parsed, all original data appears on them. Again, this is true for any browser.

Here are some of the more important known limitations:

Not a Web Browser
You cannot use IntraDOS to access the internet, and it does not work with a modem. The HTML files must be available on the user's hard drive or network. Within IntraDOS's other limitations, HTML files on the internet can be saved in the office network.

Look/Feel
IntraDOS does not support images (which are marked by è).

Extended or "special" characters are displayed based on the ASCII character set rather than the Windows set. Thus the image marker (above) appears as the Greek letter phi in IntraDOS, but as e-grave in Windows.

Colors are limited to 16 and cannot be changed by coding the HTML page. Thus links have one color (yellow) whether one has used them or not. The user can select a preferred color for the background, normal foreground, bold, italics, and H1 to H6 tags.

Only one font and font size are available. Emphasis can be accomplished only by codes such as <B>, <I>, <H1>, etc. Codes such as <Font size=+1> affect only the color of the text.

Frames are not supported. Network administrators should have IntraDOS users link to the most informative frame page.

Size of Files
IntraDOS will not handle a file that generates a screen length longer than 32,000 lines or wider than 32,000 characters. I have loaded pages with over 200 links and had no memory problems, but there is some ultimate limit on the number of links that a page can have.

Lists
Bullet-like characters in all lists are standardized by the program, not established by the HTML author.

Nesting of lists (<UL> and <OL>) is supported up to 9 levels and only so far as the left margin is less than 50% of the space available for text (i.e., fewer levels in tables). Attempts to make deeper levels of nesting will yield unpredictable results.

Due to formatting limitations, numeric ordered lists will start over at 1 after 99, and alphabetical ordered lists greater than 26 (a-z or A-Z) will repeat. For the same reason, Roman numerals are not supported in ordered lists.

Tables
Nesting of tables, i.e., one table within another, is not supported and will yield unpredictable results.

Tables wider than the screen are not supported, and will yield unpredictable results. Therefore, tables with many columns are also problematic, since space must be allowed for the cell walls and text in each. For example, a table of eight columns will leave about six letters per cell.
One less than ideal solution is the use <PRE> and </PRE> tags and place a preformatted table between them.

Tables narrower than the screen are expanded to fill the screen. Thus, text set to appear on either side of a table, but not within it, will appear elsewhere.

Tables with about 32,000 characters may cause unpredictable results. Tables whose cells exceed 16,000 characters may cause unpredicable results.
Solution: Break up your tables/cells into smaller tables/cells.

In tables with different numbers of cells per row, cells are filled with data from left to right. Thus some unusual configurations of tables are not supported.

Special formatting of tables, such as combining cells and cellpadding, is unsupported. Borders are either off (invisible) or on (single line around each cell).

Because of line width limitations, column widths are calculated without regard to command arguments such as <TD width=60%>.

Differences from IntraDOS 1.1:

-------------------------
REGISTRATION
-------------------------

This program is shareware. If you wish to use it beyond a 30 day trial period, please register your version.

The normal registration fee is $35 for a stand-alone computer, $15 per additional computer on a local network, with a maximum fee for an entire local area network of $80. Certain discounts also apply:

Register by sending a check or money order to:

Charles M. Cork, III
P. O. Box 6897
Macon, Georgia 31208-6897

Please include your name, your business's name (if applicable), your mailing address, and your e-mail address. By return e-mail or mail, you will get registration information.

Beyond the satisfaction of doing the right thing and making the registration request at the end of the program disappear, registration will entitle you to notifications of upgrades (free to registered users, unless the upgrade is really colossal) and to such support as I may be able to give via e-mail to ccork000@counsel.com.

Redistribution Limitations:

The unregistered version of IntraDOS may be freely distributed by any means so long as no included files are altered, added or deleted.

A registered user of IntraDOS at the $80 level may freely distribute the program without alteration or deletion of files, except that the Home.HTM file may be altered and other files may be added. This will allow a registered user to provide an off-line reader of the user's HTML materials.

IntraDOS

I hope that you find IntraDOS useful and worth the cost.
Charles Cork, ccork000@counsel.com

Revised 1997/11/25