Begin
File:			bhtml.tgz
Description:	Basis HTML Viewer (Bhtml_viewer)
Keywords:		Basis QNX Windows HTML hypertext document viewer reader
Version:		1.0C
Entered-date:	Sept. 22, 1997
Author:   		Frank Kolnick, Basis Computer Systems Inc.
Ported-by:
Original-site:
Copying-policy:
Supplemental:


Basis HTML Viewer (Bhtml) version 1.0C                      Sept. 22, 1997
--------------------------------------------------------------------------
Requires: QNX 4.22 or later, QNX Windows 4.23A or later.
(Revision history at end of document.)

To install:  1. copy bhtml.tgz to /windows/apps
             2. cd to /windows/apps
             3. execute:  gzip -cd bhtml.tgz | pax -vr

This shareware version of the Basis HTML Viewer will display and browse
through most standard HTML 2+ files, i.e., with many HTML 3 extensions,
including tables, links and IDs. In particular, it can display the QSSL
on-line manual set. It cannot handle huge HTML files very well and does
support interlaced GIF files. No user input is supported; this is strictly
a viewer.

A proportional system font (such as 'helv') is highly recommended. Using
a fixed-width system font limits formatting and does not allow variations
in text style (e.g., bold) and size.
You should also set the "o(I)" screen option, if possible, for optimal
display of images.

Although this program can be run standalone (taking a single file name
as an argument), it is best used through the Basis Workspace Manager (Bwm)
which will allow you to browse through directories and will automatically
execute Bhtml_viewer when you double-click on an HTML file. If the viewer
is given the pathname of a directory on its command-line, it will open a
table of contents if that directory contains '.toc' files.

The viewer requires QNX Windows version 4.23A or later, which supports
embedded formatting codes in text (see the relevant release notes). Note
that the formatting for 'fixed fonts' (for 'typewritten' text, etc.) can
be redefined through your screen.cfg file.

This package contains the following files, which should appear in
/windows/apps/Basis:

Bhtml_viewer      --  the program
Bhtml.help        --  help file for Bhtml
Bhtml.splash.pict --  'info' identification picture
Bhtml.readme      --  this file


Protocols
---------
Bhtml itself only handles local HTML files. When it encounters a reference
to a file prefixed with a 'protocol' identifier (such as "http:" or "mail:"),
it normally ignores it. However, if it finds a process named "Bhtml_proto" in
/windows/apps/Basis, it runs that program, sends it the file specification
and accepts a new file name in return. This file is assumed to contain valid
HTML code and is opened and displayed normally.
The rules for the protocol handler are simple:
- when executed, it should first check for the registered name "BHTML/proto"
  and exit if it finds it (i.e., only one copy should be running at a time)
- otherwise, it should register that name
- loop, waiting for messages
- the only message type (currently) is a simple text string containing a
  file reference (with the protocol prefix)
- process the reference, i.e., load/open/convert/etc. the file(s)
- reply with a message containing the full pathname of a new HTML file

Alternatively, if Bhtml_proto does not exist, Bhtml will look for a process
named "Bhtml_xxx" where 'xxx' is the name of the protocol (e.g., "http").
I.e., it will attempt to run the program, send it a message (as above), then
terminate it. (These programs do not register a name.)


History
-------
0.1A   - initial release
0.9A   - faster start-up
       - background defaults to the closest equivalent of a very light gray
       - supports navigation buttons (back-tracking, bookmarks, etc.)
       - supports background, text and link color definitions (hexadecimal,
         or named: aqua, black, blue, fuchsia, gray, green, lime, maroon,
         navy, olive, purple, red, silver, teal, white, yellow)
       - supports selectable images (i.e., to link to other documents)
       - supports all horizontal rule options
       - supports all list and list-item types (compact, type, start and
         value) and nested lists
       - improved table parsing (accepts rows, etc., without closing tag)
       - automatically sizes table column widths
1.0A   - new graphical 'info' window
       - accepts untagged paragraphs, i.e., not enclosed by <P>...</P>,
         and unquoted link references (i.e., 'loose' HTML coding)
       - better handling of HTML coding errors
       - handles URLs more gracefully
       - handles <BR> (line break) tags properly
       - can display very large GIF images
       - handles duplicate file names (in different subdirectories) better
1.0B   - handles references with embedded anchor names ("xxx#yyy")
       - supports optional external protocol (URL) handlers (see
         'Protocols', above)
       - if passed a directory pathname, will automatically open a table of
         contents for that directory, if possible
       - table-of-contents window is updated as documents are navigated
1.0C   - supports the <BASEFONT> and <FONT> tags (incl. face, size and color)
       - supports the <BIG> and <SMALL> tags
       - 'home' button (re)displays the TOC window if the original path (or
         the Bwm 'help_path') points to a directory


Copyright 1996-1997 Basis Computer Systems Inc. All rights reserved.
Basis Computer Systems Inc. makes no warranties, express or implied,
with respect to this software. All risk is with the user of the
software. Permission is granted to make copies of this program
available to any licensed user of QNX Windows, free of charge, provided
that this text file is included with the software, and that no files in
the distribution are modified or omitted.


End