Stop Emacs from invoking a browser (Shallow Thoughts)

Stop Emacs from invoking a browser

After upgrading my OS (in this case, to Debian sid), I noticed that my browser window kept being replaced with an HTML file I was editing in emacs. I'd hit Back or close the tab, and the next time I checked, there it was again, my HTML source.

I'm sure it's a nice feature that emacs can show me my HTML in a browser. But it's not cool to be replacing my current page without asking. How do I turn it off? A little searching revealed that this was html-autoview-mode, which apparently at some point started defaulting to ON instead of OFF. Running M-x html-autoview-mode toggles it back off for the current session -- but that's no help if I want it off every time I start emacs.

I couldn't find any documentation for this, and the obvious (html-autoview-mode nil) in .emacs didn't work -- first, it gives a syntax error because the function isn't defined until after you've loaded html-mode, but even if you put it in your html-mode hook, it still doesn't work.

I had to read the source of sgml-mode.el. (M-x describe-function html-autoview-mode also would have told me, if I had already loaded html-mode, but I didn't realize that until later.) Turns out html-autoview-mode turns off if its argument is negative, not nil. So I added it to my html derived mode:

(define-derived-mode html-wrap-mode html-mode "HTML wrap mode"
  (auto-fill-mode)
  ;; Don't call an external browser every time you save an html file:
  (html-autoview-mode -1)
)