Re: RFC: comint.el - comint-highlight-prompt and unreadable colors

[Dan Nicolaescu <dann@ics.uci.edu>]

Miles Bader <miles.bader@necel.com> writes:

  > Stefan Monnier <monnier@iro.umontreal.ca> writes:
  > > Problem is: in terminal mode, menus are also more difficult to
  > > use :-( I wish PuTTY used a special TERM setting (or alternatively, I wish
  > > the xterm control-sequences included one which can be used to identify the
  > > terminal in use, and maybe even its background color).  Maybe we should
  > > write&submit a patch to X.org (or whoever is maintaining xterm nowadays) for
  > > that, so that we can use it in Emacs-23.
  > 
  > Yeah; someone mentioned that rxvt, while it uses TERM=xterms, defines
  > some extra environment variables.  I just checked, and I see these:
  > 
  >    # black-on-white rxvt (the default)
  >    TERM="xterms"
  >    COLORFGBG="0;15"
  >    COLORTERM="rxvt"
  > 
  >    # white-on-black rxvt (rxvt -fg white -bg black)
  >    TERM="xterms"
  >    COLORFGBG="15;0"
  >    COLORTERM="rxvt"
  > 
  >    # green-on-black rxvt (rxvt -fg green -bg black)
  >    TERM="xterms"
  >    COLORFGBG="10;0"
  >    COLORTERM="rxvt"
  > 
  > Not perfect (it would be better to actually get the terminal's whole
  > colormap in absolute terms) but that seems enough for emacs to do a
  > decent job of setting up the background type at least.
  > 
  > So I think Emacs could use the above information if it's present, which
  > will cover rxvt, 

Emacs does use the above information correctly (i.e. it sets the
default background and the colormap) IFF TERM is set to: xterm,
xterm-*, rxvt or rxvt-*.

TERM=xterms is equivalent to not having any terminal initialization
code in lisp/term/*.el

Where does "xterms" come from? Is is a default setting on some
systems, or just a user that thought it would be a good idea to set
TERM to that?

  > and as you say, submit a patch to make xterm define the
  > same variables.

  > [An additional variable giving the whole colormap would be even nicer,
  > e.g.:
  > 
  >    COLORMAP="0:#000000,1:#ff0000,2:#00ff00,..."
  > 
  > Maybe we could try to submit a patch to export that info too...]

Now all the major terminal implementations support 256 colors...
(luckily except rxvt, all implement the xterm color scheme for the
colors 16-256)