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

[jari.aalto@cante.net (Jari Aalto+mail.emacs)]

* Mon 2007-03-26 Miles Bader <miles.bader AT necel.com> gmane.emacs.devel
* Message-Id: buoircowocf.fsf AT dhapc248.dev.necel.com
> Jari Aalto <jari.aalto AT cante.net> writes:
>
>> Have a look at these:
>>
>> 1) On Windows, terminal Putty, which is very popular free SSH terminal.
>>
>> http://cante.net/~jaalto/tmp/bug/emacs/m-x-shell-color--win32-putty.jpg
> ...
>> 2) On windows, displaying a rxvt terminal back to the Cygwin X11 server
>>    from a Unix host using "-bg black -fg snow"
>>
>> http://cante.net/~jaalto/tmp/bug/emacs/m-x-shell-color--rxvt-cygwin-X11.jpg
>
> In both cases it looks like Emacs doesn't realize that it's on a
> dark-background terminal, and is using light-background mode (which
> indeed defaults to a darkish blue for comint prompts).
>
> This is a common problem, because Emacs generally _cannot_ tell the
> background color on a terminal, so it has to guess; I don't know about
> windows, but on X11 it defaults to assuming dark-background on terminals
> unless the TERM environment variable is "xterm".  If TERM = "xterm",
> Emacs assumes a light background.
>
> Since rxvt sets TERM to "xterms", that's almost certainly what's
> happening in the 2nd case.  On windows, I don't know, but it's probably
> a similar problem.
>
> You can override what background mode emacs uses by customizing the
> variable `frame-background-mode'.

The problem is that many people will hit this. The putty is very
popular on Windows side. 

May I suggest that the default is changed to 'bold instead of cyan.
That would probably be more safer choice now when 22 turns colors on
by default.

Jari