bugGNU Screen - Bugs: bug #66999, Loss of functionality in screen 5.0

 
 

bug #66999: Loss of functionality in screen 5.0

Submitter:  None
Submitted:  Mon 07 Apr 2025 06:14:37 PM UTC
   
 
Category:  None Severity:  3 - Normal
Priority:  * 5 - Normal Status:  None
Privacy:  Public Assigned to:  None
Open/Closed:  Open Release:  None
Fixed Release:  None Planned Release:  None
Work Required:  None
* Mandatory Fields

Add a New Comment Rich Markup
   

Tue 08 Apr 2025 06:59:15 PM UTC, comment #2: 

The colour problem in Vim is easy to recreate.

- use an xterm with a black background, other terminals with a black background probably also work
- vim any file that has syntax highlighting
- :set bg=dark
- :colorscheme blue

for the files I tried, this turned all text invisible.

Even after exiting Vim, text was still printed in an invisible color

Rhialto <rhialto>
Mon 07 Apr 2025 06:23:59 PM UTC, comment #1: 

I had a hunch and tried the patch from https://github.com/termux/termux-packages/issues/22688 (found via https://savannah.gnu.org/bugs/?66614)

--- display.c.orig      2025-04-07 14:57:22.965161139 +0000
+++ display.c
@@ -437,6 +437,8 @@ static void RAW_PUTCHAR(uint32_t c)
 {
 
        if (D_encoding == UTF8) {
+           /* from https://github.com/termux/termux-packages/pull/23096/files */
+               c = (c & 255) | (unsigned char)D_rend.font << 8;
                if (D_mbcs) {
                        c = D_mbcs;
                        if (D_x == D_width)


and it seemed to help with the first issue.

Rhialto <rhialto>
Mon 07 Apr 2025 06:14:37 PM UTC, original submission:  

I just updated screen from 4.x to 5.0 on my system, and I noticed right away the loss of an important functionality.                                   
                                                                               
My main screen session uses Latin1 (hysterical raisins...) but sometimes I connect to it from a terminal that does utf-8.                               
                                                                               
Screen 4.x would convert this seamlessly.                                      
                                                                               
Screen 5.0 does not.                                                           
                                                                               
In particular, when using Mutt, it uses ACS characters in threaded mode, to draw lines and arrows. These characters become some totally unrelated junk characters when seen from UTF-8.                                         
                                                                              
Attached is a screen shot to show what I see. On the left is the terminal in utf-8, on the right the original in Latin-1 (ISO 8859-1).                                              

As a second matter, screen 5.0 in some cases makes characters invisible instead of coloured. For instance with syntax highlighting in Vim. This doesn't always seem to happen, I have not yet determined the precise circumstances.

Anonymous

 

(Note: upload size limit is set to 16384 kB, after insertion of the required escape characters.)

Attach Files:
   
   
Comment:
   

Attached Files
file #57112:  IMG_20250404_184457704.png added by None (736KiB - image/png - Screen shot of the first problem)

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -email is unavailable- added by rhialto (Posted a comment)
  •  

    There are 0 votes so far. Votes easily highlight which items people would like to see resolved in priority, independently of the priority of the item set by tracker managers.

    Only logged-in users can vote.

     

    Follows 1 latest change.

    Date Changed by Updated Field Previous Value => Replaced by
    2025-04-07 None Attached File- Added IMG_20250404_184457704.png, #57112

    Back to the top

    Powered by Savane 3.15-4cd8.
    Corresponding source code