Condition-Gated Unit

systemd · medium · solved in-browser (no VM needed) · 3 tiered hints

Write /etc/systemd/system/run-on-ac.service so it only starts when the machine is on AC power AND a feature file exists. In [Unit] set ConditionACPower=true and ConditionPathExists=/etc/app/enabled. In [Service] set Type=oneshot and ExecStart=/usr/local/bin/run-on-ac. (Authored config, graded structurally — the engine isn't run here.)

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