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POWERD(8) NetBSD System Manager's Manual POWERD(8)
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Maintained for NetBSD
by Kimmo Suominen.
Based on man-cgi by Panagiotis Christias.
powerd -- power management daemon for sysmon
powerd acts upon power management events posted by the kernel's power
management facility. When events are posted, powerd translates the event
into a script name and a list of arguments. powerd then runs the script
in order to implement the power management policy defined by the system
The following options are available:
-d Enable debugging mode. Verbose messages and all messages intended
for syslog(8) will be sent to stderr, and powerd will stay in the
foreground of the controlling terminal.
-n Prevent execution of power management scripts.
All configuration of powerd is encapsulated into scripts that are run
when power management events occur. The daemon will look for the scripts
from the directory /etc/powerd/scripts.
Configuration scripts are run synchronously; powerd will start the script
and wait for its completion before it handles the next event.
Configuration scripts are called with different arguments, depending on
the script class. These classes are described in the following sections.
POWER SWITCH SCRIPTS
Power switch scripts are called when a state change event occurs on a
power switch device. Power switch scripts are called with two arguments:
the device with which the event is associated, and the event type.
The following power switch script names are defined:
power_button This script is called when an event occurs on a power but-
reset_button This script is called when an event occurs on a reset but-
sleep_button This script is called when an event occurs on a sleep but-
lid_switch This script is called when an event occurs on a lid switch
acadapter This script is called when an online or offline event
occurs on an AC adapter device.
hotkey_button This script is called when an event occurs on a hotkey
The following events are defined for power switch devices:
pressed The button was pressed, the lid was closed, or the AC
adapter was connected.
released The button was released, the lid was opened, or the AC
adapter was disconnected. Note that power and sleep but-
ton devices usually do not post this type of event.
The following is an example of how a power button script might be invoked
when a power button is pressed by the operator:
/etc/powerd/scripts/power_button acpibut0 pressed
envsys(4) scripts are called when a condition was triggered in a sensor.
These scripts are called with three arguments: the device associated, the
event type, and the sensor's name. The sensor_drive and the
sensor_battery scripts uses a fourth argument: state description.
The following envsys script names are defined:
sensor_battery This script is called when an event occurs on a bat-
tery sensor (Wh/Ah/Battery state).
sensor_drive This script is called when an event occurs on a drive
sensor_fan This script is called when an event occurs on a fan
sensor_indicator This script is called when an event occurs on a indi-
sensor_power This script is called when an event occurs on a power
sensor_resistance This script is called when an event occurs on a
resistance sensor (Ohm).
sensor_temperature This script is called when an event occurs on a tem-
sensor_voltage This script is called when an event occurs on a volt-
The following events are defined for fan, indicator, power, resistance,
temperature, and voltage sensors:
critical A critical condition was triggered.
critical-under A critical under condition was triggered.
critical-over A critical over condition was triggered.
warning-under A warning under condition was triggered.
warning-over A warning over condition was triggered.
The following event is defined for all scripts, but it is only sent if
any of the previous events has been previously sent:
normal A normal state/capacity/condition was triggered.
The following events are defined only for battery sensors:
user-capacity Capacity dropped below the limit set by the user.
low-power System is running in low power. This implies that
the AC adapter is disconnected and all batteries are
in critical or low capacity. The script shutdowns
the system gracefully by default.
The following events are defined for drive and battery sensors:
state-changed The state of the sensor has been changed and it is
not in the normal state.
The following is an example of how a temperature sensor script might be
invoked when a critical over condition is triggered:
/etc/powerd/scripts/sensor_temperature lm0 critical-over "CPU Temp"
acpi(4), acpiacad(4), acpibut(4), acpilid(4), envsys(4), i386/apm(4)
powerd first appeared in NetBSD 2.0. Support to handle envsys(4) events
appeared in NetBSD 5.0.
powerd was written by Jason R. Thorpe <firstname.lastname@example.org> and
contributed by Wasabi Systems, Inc.
Juan Romero Pardines added support to handle envsys(4) events.
Due to its synchronous nature powerd cannot be trusted to handle events
within a certain time.
NetBSD 8.0 December 15, 2010 NetBSD 8.0