I’m a programmer and amateur radio operator.

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Joined 1 year ago
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Cake day: June 6th, 2023

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  • Fun fact about that: in morse code, SOS is a prosign. This means it gets its own special rules.

    Rather than being three seperate letters (… — …), it’s one letter without any letter spaces (…—…). This is something that applies to all prosigns in morse code, though most of them are just two letters long.

    Also, when sending it on repeat you just continue the pattern without any spaces. Instead of …—… …—… (with a letter space) or …—…/…—… (with a word space), you send …—…—…—…—… and just keep continuing the pattern. iirc SOS is the only prosign where this is a thing.

    Other prosigns are for example HH (…) to indicate a correction to something previously sent, and SK (…-.-) (silent key) to signal that you have finished with the current conversation and the frequency is now clear.







  • If you use btrfs snapshots and systemd-boot instead of grub, then be carefull restoring updates from before a kernel update.

    If I understand it correctly, with systemd-boot the kernel lives in the EFI partition, while the kernel modules live in the main (btrfs) partition. If you restore a snapshot with a different kernel version, it doesn’t restore the kernel itself, but the kernel modules have different filenames, which stops the system from being able to boot.

    At least that is my understanding of the problem, from having to debug it twice (just start a live-boot system and use Timeshift to restore the system to after the update again). The next time I install Linux, I think I’ll go with grub instead of systemd-boot.

    That being said, I really like btrfs snapshots as a sort of “almost backup” (still do regular backups on an external drive). They are quick and easy, and most packet managers can be setup to automatically make a snapshot before installing/updating stuff.