The
apm program communicates with the Advanced Power Management (APM) daemon,
apmd(8), making requests of the current power status or placing the system either into suspend or stand-by state. The
apm tool is only installed on supported platforms.
With no flags,
apm displays the current power management state in verbose form.
Available command-line flags are:
-z
Put the system into suspend (deep sleep) mode.
-S
Put the system into stand-by (light sleep) mode.
-l
Display the estimated battery lifetime in percent.
-m
Display the estimated battery lifetime in minutes.
-b
Display the battery status: 0 means high, 1 means low, 2 means critical, 3 means charging, 4 means absent, and 255 means unknown.
-a
Display the external charger (A/C status): 0 means disconnected, 1 means connected, 2 means backup power source, and 255 means unknown.
-s
Display if power management is enabled.
-v
Request more verbose description of the displayed states.
-f sockname
Set the name of the socket via which to contact
apmd(8) to
sockname.
-d
Do not communicate with the APM daemon; attempt instead to manipulate the APM control device directly.
The
zzz variant of this command is an alternative for suspending the system. With no arguments,
zzz places the system into suspend mode. The command line flags serve the same purpose as for the
apm variant of this command.
This command does not wait for positive confirmation that the requested mode has been entered; to do so would mean the command does not return until the system resumes from its sleep state.