[Last modified: Mar 96]

Answer: Thanks to Matthew Freedman (mattf@cac.washington.edu) and
intasoft@cix.compulink.co.u for updates to the URLs mentioned in this answer.

Ken Sall (ksall@cen.com) writes: The HTML (HyperText Markup Language) widget
is part of the NCSA Mosaic source code available from ftp.ncsa.uiuc.edu.  Look
in the "libhtmlw" subdirectory of the "Mosaic-src-*" subdirectory of:

    ftp://ftp.ncsa.uiuc.edu/Mosaic/Unix/source/

or, more generally, look for the files HTML.c, HTML.h, HTMLP.h, etc. in your
"libhtmlw" subdirectory of the Mosaic source.

For (old) documentation, see

http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/htmlwidget.html.

However, Matthew M. Freedman (mattf@cac.washington.edu) pointed out the
document is out of date: "One important thing to know is that the on-line
documentation for the Mosaic html widget is out of synch with the source code.
I e-mailed NCSA about this in May, but they seem to have ignored the report.
The one that I wasted half a day because of is HTMLSetText(). The on-line docs
list four arguments, but in fact there are seven. I have no idea what the
extra three undocumented parameters are used for, I just plugged in NULL's and
it works. The other error I noticed is that they document a "page" field in
WbAnchorCallbackData, but it does not actually exist.  Also, at least for me,
after I call HTMLSetText() the first time, the widget remains blank. I have to
lower and raise the window for it to be drawn. Anybody know what is wrong? I
guess will probably just spoof an expose in my code."


For information on using Mosaic by remote control, see

    http://www.ncsa.uiuc.edu/SDG/Software/XMosaic/CCI/cci-spec.html
and
    http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/remote-control.html


Here are more details from ah627@FreeNet.Carleton.CA (Samuel Effah):

To the numerous request for the NCSA HTML widget information.

Everything not already copyrighted by CERN is copyrighted by NCSA (including
the contents of the libhtmlw, libnet, libXmx, and src directories, but not
including the contents of libdtm, which is entirely public domain). ...

 * The UI grants you (hereafter, Licensee) a license to use the Software    *
 * for academic, research and internal business purposes only, without a    *
 * fee.  Licensee may distribute the binary and source code (if released)   *
 * to third parties provided that the copyright notice and this statement   *
 * appears on all copies and that no charge is associated with such         *
 * copies.                                                                  *
 *                                                                          *
( you can read more about the copyright in the Mosaic source code ).


Documentation on the HTML widget can be located at:

  http://www.ncsa.uiuc.edu/SDG/Software/Mosaic/Docs/htmlwidget.html
  ( it's on the older version, I think Mosaic1.x )

For starters, you can compile directory Mosaic2.4/libhtmlw for the widget.
Using: To create widget:
  htlmWid = XtCreateManagedWidget( "htlmWid",
htmlWidgetClass,                                      parent,
                                     htlmArgs,
                                     XtNumber( htlmArgs ));

Callback for anchors:
  XtAddCallback(htlmWid, WbNanchorCallback, htmlRef, NULL);

where htmlRef() looks like:

static void htmlRef(widget, client_data, call_data) Widget widget; XtPointer
client_data; WbAnchorCallbackData* call_data; {
        buffer = readHTMLFile( call_data->href );
        XtVaSetValues( widget, WbNtext, buffer, NULL ); }

where readHTMLFile() is

char * readHTMLFile( in_file ) char *in_flie; {
  /* function to read a file and return its content, given
     the file's name */ }

I think this is enough to start you off.


Thanks to: Samuel Effah