Provided by: html2wml_0.4.11+dfsg-1_all bug

NAME

       Html2Wml -- Program that can convert HTML pages to WML pages

SYNOPSIS

       Html2Wml can be used as either a shell command:

         $ html2wml file.html

       or as a CGI:

         /cgi-bin/html2wml.cgi?url=/index.html

       In both cases, the file can be either a local file or a URL.

DESCRIPTION

       Html2Wml converts HTML pages to WML decks, suitable for being viewed on a Wap device. The
       program can be launched from a shell to statically convert a set of pages, or as a CGI to
       convert a particular (potentially dynamic) HTML resource.

       Althought the result is not guarantied to be valid WML, it should be the case for most
       pages. Good HTML pages will most probably produce valid WML decks. To check and correct
       your pages, you can use W3C's software: the HTML Validator, available online at
       http://validator.w3.org and HTML Tidy, written by Dave Raggett.

       Html2Wml provides the following features:

       ·   translation of the links

       ·   limitation of the cards size by splitting the result into several cards

       ·   inclusion of files (similar to the SSI)

       ·   compilation of the result (using the WML Tools, see the section on "LINKS")

       ·   a debug mode to check the result using validation functions

OPTIONS

       Please note that most of these options are also available when calling Html2Wml as a CGI.
       In this case, boolean options are given the value "1" or "0", and other options simply
       receive the value they expect. For example, `--ascii' becomes `?ascii=1' or `?a=1'. See
       the file t/form.html for an example on how to call Html2Wml as a CGI.

       Conversion Options

       -a, --ascii
           When this option is on, named HTML entities and non-ASCII characters are converted to
           US-ASCII characters using the same 7 bit approximations as Lynx. For example, `©'
           is translated to "(c)", and `ß' is translated to "ss". This option is off by
           default.

       --[no]collapse
           This option tells Html2Wml to collapse redundant whitespaces, tabulations, carriage
           returns, lines feeds and empty paragraphs. The aim is to reduce the size of the WML
           document as much as possible. Collapsing empty paragraphs is necessary for two
           reasons. First, this avoids empty screens (and on a device with only 4 lines of
           display, an empty screen can be quite ennoying). Second, Html2wml creates many empty
           paragraphs when converting, because of the way the syntax reconstructor is programmed.
           Deleting these empty paragraphs is necessary like cleaning the kitchen :-)

           If this really bother you, you can deactivate this behaviour with the --nocollapse
           option.

       --ignore-images
           This option tells Html2Wml to completely ignore all image links.

       --[no]img-alt-text
           This option tells Html2Wml to replace the image tags with their corresponding
           alternative text (as with a text mode web browser).  This option is on by default.

       --[no]linearize
           This option is on by default. This makes Html2Wml flattens the HTML tables (they are
           linearized), as Lynx does. I think this is better than trying to use the native WML
           tables. First, they have extremely limited features and possibilities compared to HTML
           tables. In particular, they can't be nested. In fact this is normal because Wap
           devices are not supposed to have a big CPU running at some zillions-hertz, and the
           calculations needed to render the tables are the most complicated and CPU-hogger part
           of HTML.

           Second, as they can't be nested, and as typical HTML pages heavily use imbricated
           tables to create their layout, it's impossible to decide which one could be kept. So
           the best thing is to keep none of them.

           [Note] Although you can deactivate this behaviour, and although there is internal
           support for tables, the unlinearized mode has not been heavily tested with nested
           tables, and it may produce unexpected results.

       -n, --numeric-non-ascii
           This option tells Html2wml to convert all non-ASCII characters to numeric entities,
           i.e., "e" becomes `é', and "ss" becomes `ß'.  By default, this option is
           off.

       -p, --nopre
           This options tells Html2Wml not to use the <pre> tag. This option was added because
           the compiler from WML Tools 0.0.4 doesn't support this tag.

       Links Reconstruction Options

       --hreftmpl=TEMPLATE
           This options sets the template that will be used to reconstruct the `href'-type links.
           See the section on "LINKS RECONSTRUCTION" for more information.

       --srctmpl=TEMPLATE
           This option sets the template that will be used to reconstruct the `src'-type links.
           See the section on "LINKS RECONSTRUCTION" for more information.

       Splitting Options

       -s, --max-card-size=SIZE
           This option allows you to limit the size (in bytes) of the generated cards. Default is
           1,500 bytes, which should be small enough to be loaded on most Wap devices. See the
           section on "DECK SLICING" for more information.

       -t, --card-split-threshold=SIZE
           This option sets the threshold of the split event, which can occur when the size of
           the current card is between `max-card-size' - `card-split-threshold' and
           `max-card-size'. Default value is 50. See the section on "DECK SLICING" for more
           information.

       --next-card-label=STRING
           This options sets the label of the link that points to the next card.  Default is
           "[&gt;&gt;]", which whill be rendered as "[>>]".

       --prev-card-label=STRING
           This options sets the label of the link that points to the previous card.  Default is
           "[&lt;&lt;]", which whill be rendered as "[<<]".

       HTTP Authentication

       -U, --http-user=USERNAME
           Use this option to set the username for an authenticated request.

       -P, --http-passwd=PASSWORD
           Use this option to set the password for an authenticated request.

       Proxy Support

       -[no]Y, --[no]proxy
           Use this option to activate proxy support. By default, proxy support is activated. See
           the section on "PROXY SUPPORT".

       Output Options

       -k, --compile
           Setting this option tells Html2Wml to use the compiler from WML Tools to compile the
           WML deck. If you want to create a real Wap site, you should seriously use this option
           in order to reduce the size of the WML decks.  Remember that Wap devices have very
           little amount of memory. If this is not enough, use the splitting options.

           Take a look in wml_compilation/ for more information on how to use a WML compiler with
           Html2Wml.

       -o, --output
           Use this option (in shell mode) to specify an output file.  By default, Html2Wml
           prints the result to standard output.

       Debugging Options

       -d, --debug[=LEVEL]
           This option activates the debug mode. This prints the output result with line
           numbering and with the result of the XML check. If the WML compiler was called, the
           result is also printed in hexadecimal an ascii forms. When called as a CGI, all of
           this is printed as HTML, so that can use any web browser for that purpose.

       --xmlcheck
           When this option is on, it send the WML output to XML::Parser to check its well-
           formedness.

DECK SLICING

       The deck slicing is a feature that Html2Wml provides in order to match the low memory
       capabilities of most Wap devices. Many can't handle cards larger than 2,000 bytes,
       therefore the cards must be sufficiently small to be viewed by all Wap devices. To achieve
       this, you should compile your WML deck, which reduce the size of the deck by 50%, but even
       then your cards may be too big. This is where Html2Wml comes with the deck slicing
       feature. This allows you to limit the size of the cards, currently only before the
       compilation stage.

       Slice by cards or by decks

       On some Wap phones, slicing the deck is not sufficient: the WML browser still tries to
       download the whole deck instead of just picking one card at a time. A solution is to slice
       the WML document by decks.  See the figure below.

            _____________          _____________
           ⎪    deck     ⎪        ⎪   deck #1   ⎪
           ⎪  _________  ⎪        ⎪  _________  ⎪
           ⎪ ⎪ card #1 ⎪ ⎪        ⎪ ⎪  card   ⎪ ⎪
           ⎪ ⎪_________⎪ ⎪        ⎪ ⎪_________⎪ ⎪
           ⎪  _________  ⎪        ⎪_____________⎪
           ⎪ ⎪ card #2 ⎪ ⎪
           ⎪ ⎪_________⎪ ⎪             . . .
           ⎪  _________  ⎪
           ⎪ ⎪   ...   ⎪ ⎪         _____________
           ⎪ ⎪_________⎪ ⎪        ⎪   deck #n   ⎪
           ⎪  _________  ⎪        ⎪  _________  ⎪
           ⎪ ⎪ card #n ⎪ ⎪        ⎪ ⎪  card   ⎪ ⎪
           ⎪ ⎪_________⎪ ⎪        ⎪ ⎪_________⎪ ⎪
           ⎪_____________⎪        ⎪_____________⎪

             WML document           WML document
           sliced by cards        sliced by decks

       What this means is that Html2Wml generates several WML documents.  In CGI mode, only the
       appropriate deck is sent, selected by the id given in parameter. If no id was given, the
       first deck is sent.

       Note on size calculation

       Currently, Html2Wml estimates the size of the card on the fly, by summing the length of
       the strings that compose the WML output, texts and tags. I say "estimates" and not
       "calculates" because computing the exact size would require many more calculations than
       the way it is done now.  One may objects that there are only additions, which is correct,
       but knowing the exact size is not necessary. Indeed, if you compile the WML, most of the
       strings of the tags will be removed, but not all.

       For example, take an image tag: `<img src="images/dog.jpg" alt="Photo of a dog">'.  When
       compiled, the string `"img"' will be replaced by a one byte value.  Same thing for the
       strings `"src"' and `"alt"', and the spaces, double quotes and equal signs will be
       stripped. Only the text between double quote will be preserved... but not in every cases.
       Indeed, in order to go a step further, the compiler can also encode parts of the arguments
       as binary. For example, the string `"http://www."'  can be encoded as a single byte (`8F'
       in this case). Or, if the attribute is `href', the string `href="http://' can become the
       byte `4B'.

       As you see, it doesn't matter to know exactly the size of the textual form of the WML, as
       it will always be far superior to the size of the compiled form. That's why I don't count
       all the characters that may be actually written.

       Also, it's because I'm quite lazy ;-)

       Why compiling the WML deck?

       If you intent to create real WML pages, you should really consider to always compile them.
       If you're not convinced, here is an illustration.

       Take the following WML code snipet:

           <a href='http://www.yahoo.com/'>Yahoo!</a>

       It's the basic and classical way to code an hyperlink. It takes 42 bytes to code this,
       because it is presented in a human-readable form.

       The WAP Forum has defined a compact binary representation of WML in its specification,
       which is called "compiled WML". It's a binary format, therefore you, a mere human, can't
       read that, but your computer can. And it's much faster for it to read a binary format than
       to read a textual format.

       The previous example would be, once compiled (and printed here as hexadecimal):

           1C 4A 8F 03 y a h o o 00 85 01 03 Y a h o o ! 00 01

       This only takes 21 bytes. Half the size of the human-readable form.  For a Wap device,
       this means both less to download, and easier things to read. Therefore the processing of
       the document can be achieved in a short time compared to the tectual version of the same
       document.

       There is a last argument, and not the less important: many Wap devices only read binary
       WML.

ACTIONS

       Actions are a feature similar to (but with far less functionalities!) the SSI (Server Side
       Includes) available on good servers like Apache. In order not to interfere with the real
       SSI, but to keep the syntax easy to learn, it differs in very few points.

       Syntax

       Basically, the syntax to execute an action is:

           <!-- [action param1="value" param2='value'] -->

       Note that the angle brackets are part of the syntax. Except for that point, Actions syntax
       is very similar to SSI syntax.

       Available actions

       Only few actions are currently available, but more can be implemented on request.

       include

           Description
                   Includes a file in the document at the current point. Please note that
                   Html2Wml doesn't check nor parse the file, and if the file cannot be found,
                   will silently die (this is the same behavior as SSI).

           Parameters
                   `virtual=url' -- The file is get by http.

                   `file=path' -- The file is read from the local disk.

       fsize

           Description
                   Returns the size of a file at the current point of the document.

           Parameters
                   `virtual=url' -- The file is get by http.

                   `file=path' -- The file is read from the local disk.

           Notes   If you use the file parameter, an absolute path is recommend.

       skip

           Description
                   Skips everything until the first `end_skip' action.

       Generic parameters

       The following parameters can be used for any action.

       for=output format
           This parameter restricts the action for the given output format.  Currently, the only
           available format is "`wml'" (when using `html2chtml' the format is "`chtml'").

       Examples

       If you want to share a navigation bar between several WML pages, you can `include' it this
       way:

           <!-- [include virtual="nav.wml"] -->

       Of course, you have to write this navigation bar first :-)

       If you want to use your current HTML pages for creating your WML pages, but that they
       contains complex tables, or unnecessary navigation tables, etc, you can simply `skip' the
       complex parts and keep the rest.

           <body>
           <!--[skip for="wml"]-->
           unnecessary parts for the WML pages
           <!--[end_skip]-->
           useful parts for the WML pages
           </body>

LINKS RECONSTRUCTION

       The links reconstruction engine is IMHO the most important part of Html2Wml, because it's
       this engine that allows you to reconstruct the links of the HTML document being converted.
       It has two modes, depending upon whether Html2Wml was launched from the shell or as a CGI.

       When used as a CGI, this engine will reconstructs the links of the HTML document so that
       all the urls will be passed to Html2Wml in order to convert the pointed files (pages or
       images). This is completely automatic and can't be customized for now (but I don't think
       it would be really useful).

       When used from the shell, this engine reconstructs the links with the given templates.
       Note that absolute URLs will be left untouched. The templates can be customized using the
       following syntax.

       Templates

       HREF Template
           This template controls the reconstruction of the `href' attribute of the `A' tag. Its
           value can be changed using the --hreftmpl option.  Default value is
           `"{FILEPATH}{FILENAME}{$FILETYPE =~ s/s?html?/wml/o; $FILETYPE}"'.

       Image Source Template
           This template controls the reconstruction of the `src' attribute of the `IMG' tag. Its
           value can be changed using the --srctmpl option.  Default value is
           `"{FILEPATH}{FILENAME}{$FILETYPE =~ s/gif⎪png⎪jpe?g/wbmp/o; $FILETYPE}"'

       Syntax

       The template is a string that contains the new URL. More precisely, it's a Text::Template
       template. Parameters can be interpolated as a constant or as a variable. The template is
       embraced between curcly bracets, and can contain any valid Perl code.

       The simplest form of a template is `{PARAM}' which just returns the value of PARAM. If you
       want to do something more complex, you can use the corresponding variable; for example
       `{"foo $PARAM bar"}', or `{join "_", split " ", PARAM}'.

       You may read the Text::Template manpage for more information on what is possible within a
       template.

       If the original URL contained a query part or a fragment part, then they will be appended
       to the result of the template.

       Available parameters

       URL This parameter contains the original URL from the `href' or `src' attribute.

       FILENAME
           This parameter contains the base name of the file.

       FILEPATH
           This parameter contains the leading path of the file.

       FILETYPE
           This parameter contains the suffix of the file.

       This can be resumed this way:

         URL = http://www.server.net/path/to/my/page.html
                                    ------------^^^^ ----
                                        ⎪        ⎪     \
                                        ⎪        ⎪      \
                                     FILEPATH FILENAME FILETYPE

       Note that `FILETYPE' contains all the extensions of the file, so if its name is
       index.html.fr for example, `FILETYPE' contains "`.html.fr'".

       Examples

       To add a path option:

           {URL}$wap

       Using Apache, you can then add a Rewrite directive so that URL ending with `$wap' will be
       redirected to Html2Wml:

           RewriteRule  ^(/.*)\$wap$  /cgi-bin/html2wml.cgi?url=$1

       To change the extension of an image:

           {FILEPATH}{FILENAME}.wbmp

PROXY SUPPORT

       Html2Wml uses LWP built-in proxy support. It is activated by default, and loads the proxy
       settings from the environment variables, using the same variables as many others programs.
       Each protocol (http, ftp, etc) can be mapped to use a proxy server by setting a variable
       of the form `PROTOCOL_proxy'.  Example: use `http_proxy' to define the proxy for http
       access, `ftp_proxy' for ftp access. In the shell, this is only a matter of defining the
       variable.

       For Bourne shell:

           $ export http_proxy="http://proxy.domain.com:8080/"

       For C-shell:

           % setenv http_proxy "http://proxy.domain.com:8080/"

       Under Apache, you can add this directive to your configuration file:

           SetEnv http_proxy "http://proxy.domain.com:8080"

       but this has the default that another CGI, or another program, can use this to access
       external resources. A better way is to edit Html2Wml and fill the option `proxy-server'
       with the appropriate value.

CAVEATS

       Html2Wml tries to make correct WML documents, but the well-formedness and the validity of
       the document are not guarantied.

       Inverted tags (like "<b>bold <i>italic</b></i>") may produce unexpected results. But only
       bad software do bad stuff like this.

LINKS

       Download

       Html2Wml
           This is the web site of the Html2Wml project, hosted by SourceForge.net.  All the
           stable releases can be downloaded from this site.

           [ http://www.html2wml.org/ ]

       Nutialand
           This is the web site of the author, where you can find the archives of all the
           releases of Html2Wml.

           [ http://www.maddingue.org/softwares/ ]

       Resources

       The WAP Forum
           This is the official site of the WAP Forum. You can find some technical information,
           as the specifications of all the technologies associated with the WAP.

           [ http://www.wapforum.org/ ]

       WAP.com
           This site has some useful information and links. In particular, it has a quite well
           done FAQ.

           [ http://www.wap.com/ ]

       The World Wide Web Consortium
           Although not directly related to the Wap stuff, you may find useful to read the
           specifications of the XML (WML is an XML application), and the specifications of the
           different stylesheet languages (CSS and XSL), which include support for low-resolution
           devices.

           [ http://www.w3.org/ ]

       TuxMobil
           This web site is dedicated to Mobile UniX systems. It leads you to a lot of useful
           hands-on information about installing and running Linux and BSD on laptops, PDAs and
           other mobile computer devices.

           [ http://www.tuxmobil.org/ ]

       Programmers utilities

       HTML Tidy
           This is a very handful utility which corrects your HTML files so that they conform to
           W3C standards.

           [ http://www.w3.org/People/Raggett/tidy ]

       Kannel
           Kannel is an open source Wap and SMS gateway.  A WML compiler is included in the
           distribution.

           [ http://www.kannel.org/ ]

       WML Tools
           This is a collection of utilities for WML programmers. This include a compiler, a
           decompiler, a viewer and a WBMP converter.

           [ http://pwot.co.uk/wml/ ]

       WML browsers and Wap emulators

       Opera
           Opera is originaly a Web browser, but the version 5 has a good support for XML and
           WML. Opera is available for free for several systems.

           [ http://www.opera.com/ ]

       wApua
           wApua is an open source WML browser written in Perl/Tk.  It's easy to intall and to
           use. Its support for WML is incomplete, but sufficient for testing purpose.

           [ http://fsinfo.cs.uni-sb.de/~abe/wApua/ ]

       Tofoa
           Tofoa is an open source Wap emulator written in Python.  Its installation is quite
           difficult, and its incomplete WML support makes it produce strange results, even with
           valid WML documents.

           [ http://tofoa.free-system.com/ ]

       EzWAP
           EzWAP, from EZOS, is a commercial WML browser freely available for Windows 9x, NT,
           2000 and CE. Compared to others Windows WML browsers, it requires very few resources,
           and is quite stable. Its support for the WML specs seems quite complete. A very good
           software.

           [ http://www.ezos.com/ ]

       Deck-It
           Deck-It is a commercial Wap phone emulator, available for Windows and Linux/Intel
           only. It's a very good piece of software which really show how WML pages are rendered
           on a Wap phone, but one of its major default is that it cannot read local files.

           [ http://www.pyweb.com/tools/ ]

       Klondike WAP Browser
           Klondike WAP Browser is a commercial WAP browser available for Windows and PocketPC.

           [ http://www.apachesoftware.com/ ]

       WinWAP
           WinWAP is a commercial Wap browser, freely available for Windows.

           [ http://www.winwap.org/ ]

       WAPman
           WAPman from EdgeMatrix, is a commercial WAP browser available for Windows and PalmOS.

           [ http://www.edgematrix.com/edge/control/MainContentBean?page=downloads ]

       Wireless Companion
           Wireless Companion, from YourWap.com, is a WAP emulator available for Windows.

           [ http://www.yourwap.com/ ]

       Mobilizer
           Mobilizer is a Wap emulator available for Windows and Unix.

           [ http://mobilizer.sourceforge.net/ ]

       QWmlBrowser
           QWmlBrowser (formerly known as WML BRowser) is an open source WML browser, written
           using the Qt toolkit.

           [ http://www.wmlbrowser.org/ ]

       Wapsody
           Wapsody, developed by IBM, is a freely available simulation environment that
           implements the WAP specification. It also features a WML browser which can be run
           stand-alone.  As Wapsody is written in Java/Swing, it should work on any system.

           [ http://alphaworks.ibm.com/aw.nsf/techmain/wapsody ]

       WAPreview
           WAPreview is a Wap emulator written in Java. As it uses an HTML based UI and needs a
           local web proxy, it runs quite slowly.

           [ http://wapreview.sourceforge.net ]

       PicoWap
           PicoWap is a small WML browser made by three French students.

           [ http://membres.lycos.fr/picowap/ ]

ACKNOWLEDGEMENTS

       Werner Heuser, for his numerous ideas, advices and his help for the debugging

       Igor Khristophorov, for his numerous suggestions and patches

       And all the people that send me bug reports: Daniele Frijia, Axel Jerabek, Ouyang

AUTHOR

       Sebastien Aperghis-Tramoni <sebastien@aperghis.net<gt>

COPYRIGHT

       Copyright (C)2000, 2001, 2002 Sebastien Aperghis-Tramoni

       This program is free software. You can redistribute it and/or modify it under the terms of
       the GNU General Public License, version 2 or later.