IntraDOS 1.4
Intranet HTML Browser and Program Launcher for DOS

IntraDOS is an HTML browser and program launcher 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 around 300K of RAM. I created it so that DOS 386 PCs 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 use a link, click on it with a mouse or select it by typing its first letter (or tabbing to it) and then press ENTER to activate it:
New Features of IntraDOS 1.4
Other Key Features of IntraDOS
Included Files
Recommended System
Navigating the Intranet
Selecting Options
Known Limitations
How to Register
Redistribution Limitations
Information on setting up IntraDOS on a network and launching the program appears in the Setup.htm file.

New Features of IntraDOS 1.4

Browse the File System.
With the click of a button (F5), the user can generate a browsable page containing a listing of all files in the current directory, all subdirectories, and the parent directory, allowing the user to navigate the directory structure of any available drives.
Launch Applications.
The user can launch other applications by clicking on an application link, or if a file is not an application, the user can get a choice of applications with which to read the file. When the other application is ended, the screen reverts to IntraDOS at the same stage of browsing as when the other application was launched. See the discussion below.
Menus and Other Applications.
Based on these new features, users can now create menus for applications and generally have more flexibility than before. For a sample menu, see the Appmenu.HTM file that comes with the program.
Speed and Rendering.
The code for rendering pages has been overhauled, resulting in a speed increase (well, a decrease in slowness) of about 50%. The program is still not a speed demon on a 386, but it is better than before.
Type letters of links to jump to a link.
A keyboard user may now select a link by typing the first letter of the link.

Other Key Features of IntraDOS

DOS-file system support.
Unlike some DOS 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).
Imitation of Leading Windows Browers.
IntraDOS attempts to mimic the operations of leading Windows web browsers to the extent that a text-mode program can do so. See Navigating the Intranet for further details.
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) or by typing the first letter of a link to jump to it without tabbing.
Menu items (e.g., the Back button) are activated by pressing Alt+ an accelerator key (e.g., Alt+B to go back). See Navigating the Intranet for further details.
Customizable color display.
Most HTML tags (e.g., bold, italic, header, etc.) are color coded, as are hypertext links. Users can customize how those colors and the background color will be displayed. See Options for further details.
Tables support and limited frames support.
IntraDOS supports basic tables, but not nested tables. See below for a fuller discussion of tables.
IntraDOS also provides modest support for frame pages by listing links to documents in the frames and their titles and allowing users to add the links in a table of contents (for example) as menu items.
Stockpile of Pre-parsed Files.
Because IntraDOS attempts to implement many formatting codes, parsing large HTML files can be slow on a 386 PC. 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). This results in faster performance, since a 386 PC 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.) See Options for further details.

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

Included Files:

IntraDOS.EXE  The program file
IntraDOS.ICO  An icon for Windows, just in case
ID000.CFG     A default configuration settings file
README.TXT    A condensed readme file in ASCII Text
ID-Help.HTM   A help file for using IntraDOS
Home.HTM      A sample start-up file
ReadMe.HTM    This ReadMe file in HTML
Setup.HTM     Details on configuring and networking IntraDOS
AppMenu.HTM   A sample page for launching applications
HTMLTags.TXT  A file listing the HTML tags handled by IntraDOS


Setup

Recommended System

IntraDOS has been extensively tested on my office's 386 PCs 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.

Special concerns for setting the program up on a network and more technical issues are addressed in setup.htm.

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 to parse and show the file; the second is the time it took to read a pre-parsed file from the Stockpile. (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.

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

These statistics show the improvement that stockpiling files can make.


Launching IntraDOS

IntraDOS may be launched by the command line or by batch file. The syntax for calling the program is:

Intrados [/u=ABC] [BegFile.HTM]

where /u= sets the environmental variable distinguishing this user
where BegFile.HTM sets the file to display at the start.

For further details on setting up IntraDOS to run, see Setup.HTM.


Using IntraDOS

Navigating/Exploring with IntraDOS:

As with other browsers, a user can move through the information system by activating links. In IntraDOS, the links generally appear in yellow, but the currently active link appears in red. The user can navigate by the following means:

1. Mouse
A user may follow hypertext links by clicking on them with a mouse.

2. Keystrokes
IntraDOS also allows a user to follow a link without a mouse by means of the keystrokes.
* The TAB key selects the next link, and Shift+TAB selects the preceding link.
* Alternatively, the user may press the first letter of a link to select a link that is visible on the screen.
Once the link has been selected, 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.

3. Back, Ahead and Home Menu Items
These menu items function as they do with Windows browsers. "Back" (alt+b) takes the user to the immediately preceding link (even in the same document), "Ahead" (alt+a) to the one immediately next, and "Home" (alt+o) to the first one.

4. Browsing the File System
When the user presses F5 (or Alt+f, i), IntraDOS creates a page of hyperlinks to every file in the current directory, to subdirectories, and to the parent directory. There is an ultimate limit to the number of files that can be displayed in this way, but I have seen a directory of 1,300 files displayed correctly.

5. File Open Dialog Box
When the user presses Control+O (or Alt+f, o), IntraDOS provides a dialog box for selecting a file to be opened.

6. History
When the user presses Control+H (or Alt+p, h), IntraDOS provides a list of all links from the first to the last. The user can revisit any of those documents by selecting the appropriate link and clicking OK.

7. Bookmarks
The user can save the current document as a "Bookmark" or "Favorite" by pressing Control+B. Doing so will cause IntraDOS to show the file as a menu item at the bottom of the "Pages" menu, thus allowing the user to return to the same file by using the menu rather than navigating through the intranet. The bookmark can be used in later IntraDOS sessions. (It can be changed by editing the user's configuration file.)

8. Table of Contents
By pressing Control+C, the user can also automatically store every link in the current page as an entry in the "Table of Contents." The menu item "Contents" will appear, and by activating it a list of links will appear below. The links can be used until the user exits IntraDOS or supersedes those links by loading others.

Launching Applications:

By clicking on a link to an executable file, one that ends with a .EXE or .COM extension, you can launch that program from IntraDOS. When you exit that program normally, IntraDOS will return at the same place where you left it.

This gives the user to opportunity to write an HTML file with links to executables, and thus to create a menu for applications. A sample file, called AppMenu.HTM, is included in this package.

Here are some limitations.

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 speed 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 (or 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.

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 an Internet 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 local or network drives. 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 can be changed only by customizing the color selection, as discussed above, and not by coding the HTML page. Thus links have one color (yellow, or red if currently selected) whether one has used them or not.

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 only modestly supported by listing links (80 x 25 is too little room to do otherwise and have it usable). To work around this limitation, I created the Table of Content feature. A user can visit the link that contains the contents that are often intended to be persistent, create a table of contents from that document, and visit those sites by using the persistent menu items.

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 1,300 links and had no memory problems, but there is some ultimate limit on the number of links that a page can have. It read a text file of about 900,000 bytes, but it failed to read a text file about 1,200,000 bytes in size.

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 containing more than 10-12,000 bytes are rendered in stages of about 10,000 bytes and column widths are calculated based on the status of the table after the first 10,000 bytes. Unpredictable results may occur if the structure of the first 10,000 bytes does not reflect the structure of the rest of the table, or if a cell in the table contains 10,000 or more bytes, etc.

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) and there is one space between the border and the text.

Table borders in non-standard English character sets (such as ISO 8859-2) are presently not supported. Sorry.

Memory
IntraDOS runs in just over 300K of memory, but each new document, each hypertext link and target, each bookmark and each entry in the table of contents adds to the memory that IntraDOS needs. I have not yet run out of memory though loading scores of extensive pages, but there is some upper limit on the total number of pages, links, etc.


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 $25 for a stand-alone computer, $10 per additional computer on a local network, with a maximum fee for an entire local area network of $75. Certain discounts also apply:

Ministries that are engaged in 
full-time relief of the poor........free

Religious organizations and
organizations that engage in
substantial work on behalf
of the poor.........................$5

Other charities.....................$15   single computer
                                    $25   2-5 computers on a network
                                    $40   6+ computers

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 or deleted, though other files may be added.

A registered user of IntraDOS may distribute the program without alteration, except that the default start-up file (Home.HTM) may be altered or replaced as the distributor wishes, so long as the program contains the help file (ID-Help.HTM) and a readme.txt or readme.htm file that includes at least these registration and redistribution limitations.

IntraDOS

I hope that you find IntraDOS useful and worth the cost.
Charles Cork
E-Mail: ccork000@counsel.com
Updates available at the IntraDOS web site: http://www.mindspring.com/~cmcork3/intrados.htm
Revised 1997/03/18