Re: How to set background-color without damaging cut&paste ?

[Eli Zaretskii]

> Date: Wed, 4 Sep 2024 01:28:08 +0200
> From: Peter <pmc@citylink.dinoex.sub.org>
> 
> Hi,
> 
>   I'm using xterm. I want to set the background to paperwhite.
> 
> I tried this, but it makes cut&paste unuseable:
> 
> (unless (display-graphic-p)                                                   
>   
>   (if (string-equal (getenv "TERM") "xterm-256color")                         
>       (add-to-list 'default-frame-alist '(background-color . "brightwhite"))  
>       (add-to-list 'default-frame-alist '(background-color . "white")))       
>   )                                                                           
>   
> 
> Then, given a file with this content:
> 
> First Line
> Second Line
> 
> Without the color setting, I can move the mouse over the first line,
> click thrice and hold to the second line; then middle-click into a
> hexdumper gives this:
> 
> 00000000  46 69 72 73 74 20 4c 69  6e 65 0a 53 65 63 6f 6e  |First Line.Secon|
> 00000010  64 20 4c 69 6e 65 0a                              |d Line.|
> 
> However, after setting the background-color, the result is this:
> 
> 00000000  46 69 72 73 74 20 4c 69  6e 65 20 20 20 20 20 20  |First Line      |
> 00000010  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000020  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000030  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000040  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000050  0a 53 65 63 6f 6e 64 20  4c 69 6e 65 20 20 20 20  |.Second Line    |
> 00000060  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000070  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000080  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 00000090  20 20 20 20 20 20 20 20  20 20 20 20 20 20 20 20  |                |
> 000000a0  20 0a                                             | .|
> 
> It basically fills the remainder from eol to the window-border
> with spaces.
> 
> Is there an other means to set the color?

I think it doesn't matter.  What you seem to see is xterm's effort to
give you background-colored whitespace when the background is
different from the default colors.  The mouse clicks are processed by
xterm in this case, not by Emacs.

IOW, I think this is a question for xterm developers.