I hate to see what some login management software (PAM or is it elogind?) and even the Linux kernel did to the pure (non-GUI) terminals recent years.
        Often I setup my PC to have 12 pure terminals (if I could use certain newer Apple keyboards I'd make 20) and login to them all. Sometimes if you logout or maybe even login too fast (like on 12 w/no passwords) something detects an 'overload' and bans logins for maybe five minutes. Used to work fine to hold down <CTRL>d (^D) to logout but when 'mode con rates & delays' increased & decreased (respectively,) now logging out (sometimes even logging in) overloads. If I logout w/^D it goes faster than years ago, maybe making more than a page (at smallest text on 4K) logouts so something detects dozens logouts then bans logins. This might be relevant for servers, but typically not desktops: how would one disable this behaviour?
        I'm disappointed Linux kernel terminal/console scrollback was removed, and people suggest GNU screen (what about tmux?) to get scrollback (or can you compile scrollback back in?.) I see you get scrollback in screen with ^a or ^a ^[ or ^a ESC, but those seemed to do nothing. Are there any explanations/videos for screen novices/beginners how to get scrollback (or in tmux?)
        More & more SVGAlib but even fbdev things seem to stop working: I hope fbdev is still updated. I used to use pure terminal image viewers (fbi, fbv) and now one won't page down to next image anymore (10+ year old code.) Lately I even tried a terminal video player but seems fullscreen mode no longer works (or maybe doesn't enlarge 1080p to 4K.) I see there's also terminal PDF viewer, probably many other great programs.
        This is the main LQ place (in addition to LFS, Unix areas) many people still use pure terminals so I know I'm not only person disappointed to see less working on terminals as time passes.

I'm cheesed off about the disappearance of scrollback too. What's the point of a console you can't scroll? And I don't think it's much of an answer to say "Use screen". I don't use virtual consoles very often these days, but when I do, I want them to work.

8 members found this post helpful.

Screen put aside, workaround I use sometimes is pipe the output to a pager (less, more, most or even w3m).

1 members found this post helpful.

Piping to a pager isn't always an option.

fdisk /dev/sda
enter 'm' for a reminder of the menu options, and oops, much of it went off the top of the screen, and you can't use fdisk with less. tmux/screen can help with this, but it's clunky to use, and if you end up in the emergency shell of an initrd trying to fix things you're unlikely to have access to either.

Then there's the "how can you scroll back boot-time messages that appeared before the login prompt" issue: answer is you can't any more (and not everything that gets written to /dev/console is logged to /var/log/{messages,syslog} so that's not an option either.

It's seems a very small thing, but it's a major pain in the arse in many different situations.

Hazel is right, The virtual console's are now of very limited value because of this loss of functionality.

P.S. Unless I'm intending to use something ncurses-ish I often just use a M-x shell buffer in emacs.

7 members found this post helpful.

Recording a video with a cell phone has worked for me.

When a low tech solution can capture information leakage, the perceived security risk reduction by removing scrollback seems nonsensical.

4 members found this post helpful.

I didn't know that was a 'reason;' larger risks exist from not seeing scrollback--if something fails and you don't know--so anyone claiming it's a necessarily security risk on your own computer not being able to read scrollback is mentally challenged. Of course on most/all Unix (*BSD/*IllumOS) you still have all scrollback/logs...

A valid approach if you have a video recording capable cell phone to hand. I still use a clam-shell flip phone: I prefer the form factor as it fits easily in a pocket, is more robust than large screened smartphones, it goes a week between charging, and doesn't shout "high value device, please mug me!" to any passing miscreants.

I'm afraid your low tech solution is too high tech for me.

4 members found this post helpful.

Ditto for me. I always thought the whole point of Linux was to be a practical working system and this makes it less practical. If you want toys, use an iPad.

6 members found this post helpful.

Well all the kernel stuff is in dmesg, but that doesn't cover init scripts I suppose. The vga console scrollback used the vga memory and had some pretty annoying quirks anyway like vanishing if you change virtual terminals. The impression I get is that the 'security issues' with the scrollback code were mostly just that it was unmaintained and abandoned.

I use screen a bit but never really use the scrollback thing as it's a bit clumsy since it's modal. [C-a ESC] turns on copy/scrollback mode, you can then just cursor around using the cursor keys or the page up/page down keys - that's probably why it appeared to do nothing (if you do it in an xterm the title gives you a hint that the mode has changed). [ESC] quits back to normal mode. While there you can copy text using some other keys like [return] as per the man page. Screen has some other niceties like being able to leave sessions running after you log out ([C-a d], and later 'screen -r'). Never used tmux but i presume it's more or less the same.

Another option if you're running simple (non-curses) programmes is running a shell from inside emacs via [M-x shell]. That gives you full scrollback and other normal emacs buffer things.

It would be interesting to speculate why these changes are happening. For example, maybe few are using the console at all, and those who do are using it in an automated and virtualized way, not interactively.

GNU screen scrollback works fine for me. Or the script command. Or often a pipe to tee.

Of course I didn't use xterm. On a real terminal the command just makes screen say empty buffer (even though I did something like 'ls -R' of a couple pages of hundreds thousands files, or 'yes haha' a couple pages) then page and arrow keys do nothing.

People, there's always KMSCON for you, and you can configure it as replacement for agetty entries on /etc/inittab, then you get it from login.

All shiny scroll-back features there, fancy hardware accelerated drawing and it have even support for Asian languages. You know, those Chinese or Japanese ideograms.

I tested it in the past and it works quite fine.

With a caveat: apparently it has no GPM (console mouse) support. At least I for one, I did not managed to make the mouse to work.

PS. Apparently, the fbdev is dead and the kernel's guys moves on fast forward to KMS. So, better to expect that this fbdev support will be removed soon, instead of being "updated" . Yeah, you beat a dead horse...

5 members found this post helpful.

The whole point of using the consoles is they're implemented in the kernel with no external dependencies. KMSCON is a userspace terminal app that relies on pango/fontconfig/etc. It may have its niche, but I can't think of a reason why I'd choose to run KMSCON over just using a terminal emulator in a minimal X11 or a Wayland session.

3 members found this post helpful.

Looks like it started here:
https://github.com/torvalds/linux/co...a6928d9a6afd45

Lack of a maintainer seems to be the main reason. Anyone want to step up?

chris

6 members found this post helpful.

Dang good Detective Work, chris !

Thanks

-- kjh ( I miss the console software scrollback support feature occasionally when I do Kernel and QT Updates at run level 3 )

2 members found this post helpful.