poweroff.sh

#!/bin/bash

#Copyright © 2021 Benoît Boudaud https://miamondo.org/contact
#This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public
# License as published by the Free Software Foundation, either version 3 of the License, or any later version.

#This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied
# warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
# You should have received a copy of the GNU General Public License along with this program.
# If not, see <http://www.gnu.org/licenses/>

# ----------------------------------------------------------------------------------------------------------------------

poweroff=$(date -d "00:00" +%s) # Correspond à l'heure d'extinction
time_before_poweroff=$[$poweroff - $(date +%s)] # Calcul du temps restant avant extinction.

if [ $time_before_poweroff -lt 0 ] # Si le temps restant est négatif, cela signifie que l'extinction est passée.
then # Alors, on rajoute un jour (86400 secondes) et on recalcule.
    time_before_poweroff=$[($poweroff+86400) - $(date +%s)]
fi

sleep $time_before_poweroff # Le script se met en pause jusqu'à l'extinction.

# Puis, à l'heure convenue, il lance la commande rtcwake.

rtcwake -l -m off -s 25200

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