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APM(8)		       BSD/i386	System Manager's Manual			APM(8)

     apm -- control the	APM BIOS and display its information

     apm [-ablstzZ] [-d	enable]	[-e enable] [-h	enable]	[-r delta]

     The apm utility controls the Intel	/ Microsoft APM	(Advanced Power	Man-
     agement) 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 val-
	     ues 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 op-
	     tions 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 pre-
	     vent 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	sus-
	     pended, and it supports resume from suspend, then it will be re-
	     sumed 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
	     power than	full power mode, but more than suspend mode.  Some
	     laptops support resuming from this	state on timer or Ring Indica-
	     tor events.  The output of	apm tells what your laptop claims to

     -z	     Suspend the system.  It is	used by	zzz(8).

     If	no options are specified, apm displays information and current status
     of	APM in verbose mode.  If multiple display options are given, the val-
     ues are displayed one per line in the order given here.

     apmconf(8)	has been merged	in apm and thus	apm replaces all of its	func-

     apm(4), zzz(8)

     Tatsumi Hosokawa <>

     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.

BSD			       December	22, 2009			   BSD


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