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Cake day: August 4th, 2023

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  • "The Open Book is my long-standing attempt to design a comprehensible and accessible e-book reader that you can build yourself (or at least have manufactured affordably). The current edition is something I’m calling the “Abridged” or “Developer Preview” edition. It’s designed to be incredibly simple: there are 7 through-hole and 14 surface mount components, nearly all in a chunky 1206 package that’s easy to hand solder. The tradeoff is that it has no LiPo charging circuit; instead it uses AAA batteries, making it a bit more chunky than previous versions of the book.

    The goal with this version is to get hardware in hands so we can start hacking on firmware."

    https://www.oddlyspecificobjects.com/projects/openbook/

    So:

    • This is a hobby / project of love
    • The current focus is on hardware

    I’m sure that the eventual plan is to support ePub.

    I’m not sure it will ever get there, because it’s not a well resourced project, but I personally don’t like criticizing one person’s efforts, which they are making freely available.



  • More than a decade ago a user came into #ubuntu-server on Freenode (now libera.chat ) and said that they had accidentally run “rm -rf /* something*” in a root shell.

    Note the errant space that made that a fatal mistake. I don’t remember how far it actually got in deleting files, but all of /bin/ /sbin/ and /usr/ were gone.

    He had 1 active ssh connection, and couldn’t start another one.

    It was a server that was “in production”, was thousands of miles away from him, and which had no possibility for IPMI / remote hands.

    Everyone (but me) in the channel said that he was just SoL and should just give up.

    I stayed up most of the night helping him. I like challenges and I like helping people.

    This was in the sysv-init (maybe upstart) days, and so a decent number of shell scripts were running, and using basic *nix commands.

    We recovered the bash binary by running something along the lines of

    bash_binary_contents="$( </proc/self/exe)"
    printf "%s" > /tmp/bash
    

    (If you can access “lsof” then “sudo lsof | grep deleted” will show you any files that are open, but also “deleted”. You may be surprised at how many there are!)

    But bash needed too many shared libraries to make that practical.

    Somehow we were able to recover curl and chmod, after which I had him download busybox-static. From there we downloaded an Ubuntu LiveCD iso, loop mounted it, loop mounted the squashfs image inside the iso, and copied all of /bin/ , /sbin/ , /etc , and so on from there onto his root FS.

    Then we re-installed missing packages, fixed up /etc/ (a lot of important daemons, including the one that was production critical, kept their configuration files open, and so we were able to use lsof to find the magic symlinks to them in /proc/$pid/fd/ and just cp them back into /etc/.

    We were able to restart openssh-server, log in again, and I don’t remember if we were brave enough to test rebooting.

    But we fucking did it!

    I am certainly getting a lot of details wrong from memory. It’s all somewhere at irclogs.ubuntu.com though. My nick was / is Jordan_U.

    I tried to find it once, and failed.


  • It’s at least gotten a bit better.

    There was a time when Photoshop and other programs used a copy-protection scheme that overwrote parts of grub, causing the user not to be able to boot Linux or Windows.

    They knew about it, and just DGAF. I don’t remember their exact FAQ response, but it was something along the lines of “Photoshop is incompatible with GRUB. Don’t dual boot if you use Photoshop.”

    Grub still has code for BIOS based installs that uses reed-solomon error correction at boot time to allow grub to continue to function even if parts of its core.img were clobbered by shitty copy protection schemes for Windows software.









  • I tried to solve these cross-distro compatibility problems in a generic way with this “standard”, more years ago than I’d like to think about:

    https://www.supergrubdisk.org/wiki/Loopback.cfg

    If someone wants to come up with a bootloader agnostic solution rather than one tied to grub, like an extension to Bootloader spec , https://www.freedesktop.org/wiki/Specifications/BootLoaderSpec/ , I’d be happy to evangelize it and add support to grub for using it.

    I’m not aware of any other bootloader that supports reading a config file that exists within an iso though, and secure boot support may add additional complications.

    Bottom line:

    I feel like we could relatively easily get to a point where every Live iso that actually supports loop booting can just be added, as a file, to your USB drive (from Windows, or your android phone even) and be detected at boot in a nice little menu, no editing of config files needed.

    I don’t have the time or spoons to get the Linux community there alone, but if people are interested in helping I’m more than happy to pick this up again.

    (Note: Please don’t blindly suggest “Just chain load the iso!” Things aren’t that easy, unfortunately).





  • Interstellar_1@pawb.social

    Sorry again. I wrote this last comment (and this one, TBH) from my phone and “–iso=s” should have been “–iso-8601=s” . I’ve edited my comment and the command should now work (Making a backup of your grub.cfg containing the date, to the second, in the filename. I did that to hopefully avoid you running the same command again after trying some fixes and accidentally clobbering your backup).