Bug#1010806: apt: Avoid color output on monochrome terminals

[Adam Borowski <kilobyte@angband.pl>]

On Tue, May 10, 2022 at 02:38:40PM +0200, Axel wrote:
> The apt command shows colors on monochrome terminals (even on a dumb terminal),
> please avoid this. Included is a patch which i believe will solve the problem
> and only allows output on terminals which actually have 'color' in them; the
> same logic as to when to color the default bash prompt.
> I have not tested this patch.

> --- private-output.cc.orig	2022-05-10 14:18:27.611767218 +0200
> +++ private-output.cc	2022-05-10 14:20:17.511703336 +0200
> @@ -86,7 +86,8 @@
>        SigWinch(0);
>     }
>  
> -   if(!isatty(1))
> +   char *term = getenv("TERM");
> +   if(!isatty(1) || strstr(term, "color") == NULL)
>     {
>        _config->Set("APT::Color", "false");
>        _config->Set("APT::Color::Highlight", "");

You mean monochrome terminals such as "xterm", "rxvt", "linux", ...?

I haven't seen an actual monochrome terminal since the first half of the
90's.  But even those accepted color codes and gracefully ignored them.
To find a terminal that speaks a different language you'd need to go
another decade into the past.

Thus, I guess that what you want is some global switch to disable color
in programs.  But there's no common characteristic of a terminal that'd
allow autodetecting your wishes.


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