Re: 80-column marker minor mode?

On 2009-08-12 10:15 (+0200), Sebastian Waschik wrote:
Paul Miller <neokosmos@xxxxxxxxx> writes:
I'm currently using GNU Emacs with the GTK interface (GTK+
Version 2.16.0). What I'm looking for is a minor mode that will
display a vertical line that marks the 80th (or whichever) column so
I have a simple visual cue when my lines are getting a bit long.

is it enough to mark all long lines? Then hi-lock-mode might help
you. Try the following:
(highlight-regexp "^.\\{81,\\}$")

That, too, can be done with the new whitespace-mode:

(let ((whitespace-line-column 80) ;80 is the default
(whitespace-style '(lines-tail))) ;or '(lines) for the whole line
(whitespace-mode 1))