I think the consensus here is option #2. That's what I would do or something similar.
For #3, I wouldn't fool with Chron - just calculate number of seconds until next run and sleep() that long. That way if the system restarts, your process runs immediately and calculates the time until the next run time. That way there is no Chron file involved.

I have a Raspberry Pi. I am just starting to play with it - so I am a Pi newbie. I need more hardware to do what my intended app needs to do (record HDMI video input). My Pi doesn't have a clock chip in it. When it restarts it needs to get the time/date either from me by me typing it in or via the internet. Your app depends upon knowing the current time - what happens if that time isn't known?

There might be some startup race conditions after a power failure. I'm not sure about the Pi config options are when the Pi cannot get current date/time from the internet? Maybe Pi is "ready" before the router to the internet?

Think about a status LED - perhaps blinking means good - stuck on(or off) means bad.

In reply to Re: Continuous or timed? by Marshall
in thread Continuous or timed? by Bod

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