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APM(8) FreeBSD System Manager's Manual (i386) APM(8)
NAME
apm - control the APM BIOS and display its information
SYNOPSIS
apm [-ablstzZ] [-d enable] [-e enable] [-h enable] [-r delta]
DESCRIPTION
The apm utility controls the Intel / Microsoft APM (Advanced Power
Management) BIOS and displays the current status of APM on laptop PCs.
The options are as follows:
-a Display the current AC-line status as an integer value. The
values 0, 1 and 2 correspond to the "off-line" state, "on-line"
state or "backup power" state, respectively.
-b Display an integer value reflecting the current battery status.
The values 0, 1, 2, 3, correspond to the "high" status, "low"
status, "critical" status, "charging" status respectively.
-d enable
Disable/enable suspending of the display separately from a normal
suspend using the boolean value for enable. This feature seems
to not work on many different laptops, including the Libretto
30CT and 50CT.
-e enable
Enable or disable APM functions of the computer, depending on the
boolean enable argument.
-h enable
Depending on the boolean value of enable, enable or disable the
HLT instruction in the kernel context switch routine. These
options are not necessary for almost all APM implementations, but
for some implementations whose "Idle CPU" call executes both CPU
clock slowdown and HLT instruction, -h false is necessary to
prevent the system from reducing its peak performance. See
apm(4) for details.
-l Display the remaining battery percentage. If your laptop does
not support this function, 255 is displayed.
-r delta
Enable the resume wakeup timer, if the laptop supports it. This
does not actually suspend the laptop, but if the laptop is
suspended, and it supports resume from suspend, then it will be
resumed after delta seconds (from when you run this command, not
from when you suspend).
-s Display the status of the APM support as an integer value. The
values 0 and 1 correspond to the "disabled" state or "enabled"
state respectively.
-t Display the estimated remaining battery lifetime in seconds. If
it is unknown, -1 is displayed.
-Z Transition the system into standby mode. This mode uses less
If no options are specified, apm displays information and current status
of APM in verbose mode. If multiple display options are given, the
values are displayed one per line in the order given here.
NOTES
apmconf(8) has been merged in apm and thus apm replaces all of its
functionality.
SEE ALSO
apm(4), zzz(8)
AUTHORS
Tatsumi Hosokawa <hosokawa@jp.FreeBSD.org>
BUGS
Some APM implementations do not support parameters needed by apm. On
such systems, apm displays them as unknown.
Some APM implementations cannot handle events such as pushing the power
button or closing the cover. On such implementations, the system must be
suspended only by using apm or zzz.
FreeBSD 14.0-RELEASE-p11 December 22, 2009 FreeBSD 14.0-RELEASE-p11