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Welcome to my blog, which was once a mailing list of the same name and is still generated by mail. Please reply via the "comment" links.

Always interested in offers/projects/new ideas. Eclectic experience in fields like: numerical computing; Python web; Java enterprise; functional languages; GPGPU; SQL databases; etc. Based in Santiago, Chile; telecommute worldwide. CV; email.

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[Computing] Automatic Wake (Linux)

From: andrew cooke <andrew@...>

Date: Wed, 6 Sep 2023 08:04:55 -0300

I want my computer to hibernate (or even to power off), but also to
wake automatically to check for email.  To do this I:

1 - configure Gnome to hibernate after some period (eg 1 hour)

2 - add the following cronjob:

    30 * * * * sudo rtcwake -u -m no -t `date -d 'tomorrow 00:00' '+\%s'` >& /dev/null

    which at half-past every hour sets an alarm to wake the computer
    at midnight.

This means that at midnight the computer starts and runs for an hour.
During that time, the alarm is set for the next day, then the computer
hibernates.

In this way the computer cycles every 24 hours (this starts even from
soft power off).

Obviously you could do something similar with smaller intervals if you
wanted, as long as you remember that only one alarm can be set at any
one time.

Andrew

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