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Linux console_codes man page, section 4 https://man7.org/linux/man-pages/man4/console_codes.4.html https://man7.org/linux/man-pages/man4/console_codes.4.html

by rascul 5y ago

rbanffy 5y ago
Would be cool if the console did bold, italics, underline, and, my favourite, overline.
- woodruffw 5y ago
  Bold, italics, and underline should all work in most terminal emulators! I'm not sure about overline, but strikethrough should also work.
  - derefr 5y ago
    I think the parent poster's point was that the Linux console framebuffer renderer in particular, is not a particularly full-featured terminal in terms of the SGR sequences it supports. Which can be slightly unpleasant when you're stuck working in "text" (really, console framebuffer) mode in Linux for whatever reason. (Which makes me wonder: is there a way to tell Linux to not use its own console framebuffer driver for displaying TTYs, but rather to instead spawn some userland libsdl binary and connect it to the raw framebuffer? If so, we could presumably just drop in a fully-featured terminal emulator to act as the Linux console.)
    - nitrogen 5y ago
      I seem to recall there being an fbdev-based terminal emulator that does just take over a VT, maybe it was this one: https://www.systutorials.com/docs/linux/man/1-fbterm/ https://www.systutorials.com/docs/linux/man/1-fbterm/ but searches show a couple of possibilities. I'm not sure how it works with systemd, but back in init land you could just replace the getty lines in /etc/inittab with whatever you wanted to use on that VT, or replace the default login command. What you wonder should be possible. Source: Quite a long time ago I believed that the Linux framebuffer was the future of development, and spent a lot of time making animated bootup sequences, custom login screens, writing libraries (in collaboration with others) to make development easier without having to go into a "framework" like DirectFB, and using elinks (or was it links2?) for browsing and fbi for image and PDF viewing.
      - derefr 5y ago
        > Quite a long time ago I believed that the Linux framebuffer was the future of development Hey, most of the Linux-based "retro portables" are running a pure "libsdl with Linux framebuffer backend" userland. So it was at least the future of something.
      - rascul 5y ago
        > and using elinks (or was it links2?) I believe it was links. It had numerous backends from what I recall, to include fb, X, and maybe even svgalib. I don't recall elinks supporting any of that. But I could be wrong.
      - rbanffy 5y ago
        I did a little digging into the VGA text mode hardware interface and it'd be possible to do proper bold and italics support by loading a second font and reusing the line drawings (which shouldn't italicize) and block graphics (that shouldn't bold) for additional styled symbols. Computing bold is a simple matter of OR'ing a bit-shifted character and, for italics, you can shift the top third one bit to the right and the bottom third one bit to the left. We used to do that in the 8-bit era when having three bitmap fonts took too much disk space. With the frame buffer, it should be much easier.
    - zokier 5y ago
      > is there a way to tell Linux to not use its own console framebuffer driver for displaying TTYs, but rather to instead spawn some userland libsdl binary and connect it to the raw framebuffer? That's almost how frecon (and kmscon/systemd-consoled before it) works. https://chromium.googlesource.com/chromiumos/platform/frecon/+/refs/heads/master/README.md https://chromium.googlesource.com/chromiumos/platform/frecon...
      - derefr 5y ago
        Cool, that's exactly the type of thing I was picturing. Is this used or packaged in any major Linux distribution besides ChromiumOS? I'd like to try out living inside this for a while (probably in a fullscreened VM) but CrOS is a bit too restrictive/unfamiliar as a userland for me to want to attempt it there. I guess Crouton exists, but I'd be afraid that Crouton would add an additional layer of impedance-mismatch to the VT that isn't there when just using it raw (like the kind you get when using tmux-in-ssh-in-tmux.)
        zokier 5y ago
        https://aur.archlinux.org/packages/kmscon-patched-git/ https://aur.archlinux.org/packages/kmscon-patched-git/ Maybe? I haven't tried it
  - rbanffy 5y ago
    Overline works on the most common modern Linux default graphical terminals and is supported by tmux. It’s great for terminal status lines. As pointed out, this refers to the Linux framebuffer console.
- floatingatoll 5y ago
  I'd chip in a few bucks for a Patreon supporting someone patching that functionality into the Linux framebuffer console. I don't use Linux on a monitor right now, but typography deserves that chance, and much of my career is thanks to the Linux console.

Linux console_codes man page, section 4 https://man7.org/linux/man-pages/man4/console_codes.4.html https://man7.org/linux/man-pages/man4/console_codes.4.html

by rascul 5y ago

Linux console_codes man page, section 4 https://man7.org/linux/man-pages/man4/console_codes.4.html https://man7.org/linux/man-pages/man4/console_codes.4.html

rbanffy 5y ago

Would be cool if the console did bold, italics, underline, and, my favourite, overline.

woodruffw 5y ago
Bold, italics, and underline should all work in most terminal emulators! I'm not sure about overline, but strikethrough should also work.
- derefr 5y ago
  I think the parent poster's point was that the Linux console framebuffer renderer in particular, is not a particularly full-featured terminal in terms of the SGR sequences it supports. Which can be slightly unpleasant when you're stuck working in "text" (really, console framebuffer) mode in Linux for whatever reason. (Which makes me wonder: is there a way to tell Linux to not use its own console framebuffer driver for displaying TTYs, but rather to instead spawn some userland libsdl binary and connect it to the raw framebuffer? If so, we could presumably just drop in a fully-featured terminal emulator to act as the Linux console.)
  - nitrogen 5y ago
    I seem to recall there being an fbdev-based terminal emulator that does just take over a VT, maybe it was this one: https://www.systutorials.com/docs/linux/man/1-fbterm/ https://www.systutorials.com/docs/linux/man/1-fbterm/ but searches show a couple of possibilities. I'm not sure how it works with systemd, but back in init land you could just replace the getty lines in /etc/inittab with whatever you wanted to use on that VT, or replace the default login command. What you wonder should be possible. Source: Quite a long time ago I believed that the Linux framebuffer was the future of development, and spent a lot of time making animated bootup sequences, custom login screens, writing libraries (in collaboration with others) to make development easier without having to go into a "framework" like DirectFB, and using elinks (or was it links2?) for browsing and fbi for image and PDF viewing.
    - derefr 5y ago
      > Quite a long time ago I believed that the Linux framebuffer was the future of development Hey, most of the Linux-based "retro portables" are running a pure "libsdl with Linux framebuffer backend" userland. So it was at least the future of something.
    - rascul 5y ago
      > and using elinks (or was it links2?) I believe it was links. It had numerous backends from what I recall, to include fb, X, and maybe even svgalib. I don't recall elinks supporting any of that. But I could be wrong.
    - rbanffy 5y ago
      I did a little digging into the VGA text mode hardware interface and it'd be possible to do proper bold and italics support by loading a second font and reusing the line drawings (which shouldn't italicize) and block graphics (that shouldn't bold) for additional styled symbols. Computing bold is a simple matter of OR'ing a bit-shifted character and, for italics, you can shift the top third one bit to the right and the bottom third one bit to the left. We used to do that in the 8-bit era when having three bitmap fonts took too much disk space. With the frame buffer, it should be much easier.
  - zokier 5y ago
    > is there a way to tell Linux to not use its own console framebuffer driver for displaying TTYs, but rather to instead spawn some userland libsdl binary and connect it to the raw framebuffer? That's almost how frecon (and kmscon/systemd-consoled before it) works. https://chromium.googlesource.com/chromiumos/platform/frecon/+/refs/heads/master/README.md https://chromium.googlesource.com/chromiumos/platform/frecon...
    - derefr 5y ago
      Cool, that's exactly the type of thing I was picturing. Is this used or packaged in any major Linux distribution besides ChromiumOS? I'd like to try out living inside this for a while (probably in a fullscreened VM) but CrOS is a bit too restrictive/unfamiliar as a userland for me to want to attempt it there. I guess Crouton exists, but I'd be afraid that Crouton would add an additional layer of impedance-mismatch to the VT that isn't there when just using it raw (like the kind you get when using tmux-in-ssh-in-tmux.)
      - zokier 5y ago
        https://aur.archlinux.org/packages/kmscon-patched-git/ https://aur.archlinux.org/packages/kmscon-patched-git/ Maybe? I haven't tried it
- rbanffy 5y ago
  Overline works on the most common modern Linux default graphical terminals and is supported by tmux. It’s great for terminal status lines. As pointed out, this refers to the Linux framebuffer console.
floatingatoll 5y ago
I'd chip in a few bucks for a Patreon supporting someone patching that functionality into the Linux framebuffer console. I don't use Linux on a monitor right now, but typography deserves that chance, and much of my career is thanks to the Linux console.