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APM(8)                  FreeBSD System Manager's Manual                 APM(8)

     apm, zzz -- 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
     zzz utility suspends the system by controlling APM.

     The following options are available for apm (no options are available for
     zzz).  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.

     -a      Display the current AC-line status as an integer value.  The val-
             ues 0 and 1 correspond to the ``off-line'' state or ``on-line''
             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
             doesn't actually suspend the laptop, but if the laptop is sus-
             pended, 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
             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 equivalent to zzz.

     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.

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


     Tatsumi Hosokawa <>

FreeBSD 4.10                   November 1, 1994                   FreeBSD 4.10


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