• Björn TantauOPA
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    13 hours ago

    Systemd at its core starts stuff when your Linux system boots and during normal operation. It can also start stuff at specific times. That was traditionally done by cron.

    But of course when you set up to run something at midnight it cannot run if the system is in standby. But with the WakeSystem=true option you can tell it to basically set an alarm for the computer to turn itself back on and do whatever you want it to do.

    It does not turn your computer back to sleep, though. That’s something you have to script yourself.

    I hope they add the ability to turn the computer on even if it is completely shut off. That would make keeping my family’s computers updated much easier.

    • KaninchenSpeed@sh.itjust.works
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      10 hours ago

      I hope they add the ability to turn the computer on even if it is completely shut off. That would make keeping my family’s computers updated much easier.

      That’s probably not possible, but you could do it with a microcontroller and a relay bridging the power switch.

      • Björn TantauOPA
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        3 hours ago

        If you read the corresponding feature request it actually seems to be pretty easy. They were just arguing about implementation details.

        Windows has supposedly also done this for a while now.

        Of course it depends on hardware capabilities. But I guess it’s common enough now.

        Edit: This is actually trivial to implement with the rtcwake command. Usually available in linux-utils or similar packages. rtcwake --list-modes shows you what modes your system supports.

        Edit 2: Like, this is beyond trivial. Just echo the desired waketime as a Unix timestamp to /sys/class/rtc/*/wakealarm and you’re set. Doesn’t matter if the system is just sleeping or turned off entirely.

        Edit 3: But waking from power down seems not to be supported on the Steam Deck. Only from suspend.