Section: User Commands (1)
Updated: 12 March 2018
on_ac_power - test whether computer is running on AC power
checks whether the system is running on abundant power (such as AC mains,
an USB charger, etc), as opposed to battery power.
0 (true) System is on mains power
1 (false) System is not on mains power
255 (false) Power status could not be determined
The vast majority of desktops and servers have no power sensors, thus
they return 255 "unknown"; for most purposes you'd want to consider
this answer to imply mains power --- note that 255 evaluates as false
for the shell.
This program currently provides only information known to the kernel;
it doesn't (yet?) query userspace daemons such as nut which may provide
This manual page was written by Steve Dodd <email@example.com
was updated by Thomas Hood then by Adam Borowski.