I want to have a working Visual C++ 6.0 sample code which shows how I
can intercept and modify HTML code from a browser window after it has
been navigated but before it has been shown or processed.  More
specifically I want to be able to modify <SCRIPT> elements as I see
fit before they are executed in any way by the browser.

You need to look into ActiveX for this.

Any chance you could be a bit more specific?  Do I need to write an
object which somehow gets loaded with the page?  Would I set that up
with an OnLoad command?  How can I do that before the page is
processed?  Any other hints, re: activeX ?

Can't be done. Not directly in a browser, anyway.

If the browser is loading the page, you can arrange to get
notifications at various points during the load. However, elements in
the page are added asynchrounously as the browser receives them, and
there's no notification you can subscribe to in order to find out when
individual elements are added.

You could, for example, attach to the body.onLoad event, but, by the
time this event fires, all script blocks will have been parsed and
loaded, and any global-scope code will have already executed.

You could fetch the page yourself (using WinHTTP or WinINET APIs),
modify it, and then write the result into the browser using
document.write() on an empty page.

To call functions like document.write(), you will need to obtain the
root DOM object, and then procede to make calls on that object using
the IDispatch (or IDispatchEx) interface.

Oh. And you can also attach to nagivation events too. So. The plot summary:

Catch navigation events. Intercept them and cancel them.

Take the intercepted URL, load the contents yourself. 

Clear the document. 

Write the modified contents using document.write().

There are other challenges: e.g. do you want to preserve POSTed URLs
as well as GET-ed URLs? (i.e. do you want forms processing to work
properly). This is solvable, but will probably require a fair bit of
work.

Thank you so much, at least I can stop beating my head against the
wall trying to control IE, I guess I'll consider doing what you've
suggested, I write a search toolbar with the added feature of
controlling popups but its not a perfect world, primarily because I
don't know the source of NewWindow2() calls, but also there are new
methods of causing popups that don't get caught by NewWindow2().

Thanks mucho!