Provided by: apmd_3.2.2-3ubuntu2_i386 bug

NAME

       apmd - Advanced Power Management (APM) daemon

SYNOPSIS

       apmd  [  -TVWciqv  ]  [ -P program ] [ -T seconds ] [ -c seconds ] [ -p
       percent ] [ -v level ] [ -w percent ]

DESCRIPTION

       apmd is an monitoring daemon for the Advanced  Power  Management  (APM)
       subsystem.   The  APM  subsystem consists of power-management hardware,
       firmware usually referred to as the  APM  BIOS  and  a  driver  in  the
       operating  system  kernel.  The daemon can execute a program (usually a
       shell script) when events are reported by the APM subsystem,  and  will
       log,  via  syslogd(8),  certain  changes  in  power  status.   When the
       available battery power becomes very low it can alert the user.

       When the APM subsystem notifies the daemon  of  a  pending  suspend  or
       standby  request, apmd will run a proxy program, log the event, sync(2)
       data to the disk and then  tell  the  APM  subsystem  to  continue  its
       operation.

       Preparations  for  power management events are made mainly by the proxy
       program specified using the -P option.  The proxy  program  is  invoked
       with one or two arguments:

       start  Invoked when the daemon starts.

       stop   Invoked when the daemon stops.

       standby ( system | user )
              Invoked  when  the  APM  subsystem reports that standby has been
              initiated.  The  second  parameter  indicates  whether  firmware
              ("system") or software ("user") was the originator of the event.

              The "standby" mode conserves power but leaves the  machine  able
              to  respond  almost  immediately to user activity.  Most laptops
              can’t stay in standby mode on battery power for more than a  few
              hours  or  a day.  Normally, nothing special needs to be done to
              prepare for "standing by".

       suspend ( system | user )
              Invoked when the APM subsystem reports that suspension has  been
              initiated.   The  second  parameter  indicates  whether firmware
              ("system") or software ("user") was the originator of the event.

              The  "suspend"  mode aggressively conserves power.  Usually this
              involves shutting off power to all devices except the  CPU  core
              and  memory,  which  are  put  into a very low power mode.  Most
              laptops can stay  suspended,  using  battery  power  alone,  for
              several  days.  ("Hibernation" is a kind of super-suspend, where
              all that state is written to disk and the machine uses no power.
              Hibernation is treated like suspension by the APM subsystem.)

              Before  suspending, PCMCIA devices may need to be disabled using
              cardctl(8), and some modular  device  drivers  may  need  to  be
              unloaded  if  they  have  not  been  designed  to  support power
              management.

       resume ( suspend | standby | critical )
              Invoked when the APM subsystem reports that computer has resumed
              normal  operation.   The  second parameter indicates the kind of
              event from which the system is resuming.  (A "critical"  suspend
              is a suspension that the APM subsystem performs in an emergency.
              Some kernels do not pass this event  to  user  space.   If  apmd
              receives   the  event,  it  acknowledges  the  event  and  exits
              immediately without logging or running the proxy program.)

              When resuming, PCMCIA devices may need to  be  re-enabled  using
              cardctl(8),  and  some  modular drivers may need to be reloaded.
              Note that in the case of a critical suspend,  the  system  state
              may not have been completely saved.

       change power
              Invoked when the APM subsystem reports a change in power status,
              such as a switch from mains to battery power.

       change battery
              Invoked when the APM subsystem reports that the charge of one or
              more  batteries  is  low.   A  few  minutes of battery power may
              remain.

       change capability
              Invoked when the APM subsystem  reports  some  change  in  power
              management  capabilities.   It may have been caused by operation
              of a setup  utility,  or  by  the  installation  or  removal  of
              devices.

       apmd  emits  various  messages,  most  of  which  are self-explanatory.
       Battery status log entries contain three fields, separated  by  commas.
       The  first  field  indicates how full the battery is as a percentage of
       its capacity.  The  second  field  indicates  whether  the  battery  is
       charging,  not  charging,  or discharging.  When possible, apmd adds in
       parentheses its estimate of the rate of charging or  discharging.   The
       third field indicates how much time the battery can or could be used to
       power the computer.  This information is provided by the APM subsystem.
       When possible, apmd adds in parentheses its own estimate of the battery
       life (if discharging) or of the time required  to  charge  the  battery
       fully (if charging).

OPTIONS

       -P program, --proxy program
              Specifies the proxy program to execute when events are received.
              See above for information about the arguments supplied  to  this
              program.

       -T [seconds] , --proxy-timeout [seconds]
              Sets  a  time-out  for  the proxy.  Without this option (or with
              this option and a negative argument) apmd waits indefinitely for
              the  proxy  to  finish.  If the proxy enters an infinite loop or
              wait then the machine may  appear  to  have  crashed.   If  this
              option  is given a positive integer argument then apmd will wait
              only that many seconds for the proxy to finish, after  which  it
              will  log a warning, kill the proxy, and continue processing the
              event.  The default is 30 seconds.

       -V, --version
              Prints the version of the apmd program.

       -W, --wall
              In addition to logging low battery status (as determined  either
              by  the -w level or by the firmware) using syslog(2), apmd will,
              given this option, also use wall(1) to alert all users.  This is
              most  useful if syslogd(8) is not set up to write ALERT messages
              to all users.  If both methods are used, more warnings  will  be
              made during the critical time period.

       -c [seconds] , --check [seconds]
              Controls  how  many  seconds to wait for an event.  Without this
              option (or with this option and a negative argument) apmd  waits
              indefinitely  for  an event.  If this option is given a positive
              integer argument then apmd will  wait  only  that  many  seconds
              before  checking  the  battery  level and possibly sending out a
              warning, calling the proxy or making an entry in the  log.   The
              default is 30 seconds.

       -i, --ignore-bios-battery-low
              Causes  apmd  to  ignore  a  LOW  BATTERY signal sent by the APM
              subsystem.  Some firmware signals a low  battery  at  the  wrong
              time.   Note  that  LOW BATTERY events may still be generated by
              apmd itself based on the warning level.

       -p percent, --percentage percent
              Controls how often the battery status is logged.  A new line  is
              printed  each time the battery content changes by percent_change
              if logging is enabled.  The default is 5.  Use a  value  greater
              than 100 to disable periodic logging of the battery level.

       -q, --quiet-bios-battery-low
              Causes  apmd not to generate a warning when a LOW BATTERY signal
              is received from  the  APM  subsystem.   The  firmware  on  some
              machines  produces  an audible warning when power is about to be
              used up, so an extra warning may not be needed.

       -v [level] , --verbose [level]
              The  daemon  can  generate  messages  of  varying   degrees   of
              unimportance.   Each  message  is  assigned  one of the priority
              levels defined for the  syslogd(8)  subsystem,  ranging  from  0
              (EMERG, least unimportant) to 7 (DEBUG, most unimportant).  This
              option  sets  the  threshold  level  above  which  messages  are
              suppressed.   Without an argument it increments the threshold by
              1, thus making apmd more verbose.  The default is 5 (NOTICE).

       -w percent, --warn percent
              When the battery is not being charged and  the  battery  content
              falls below the specified percent of capacity, and no such event
              has yet occurred in the current discharge cycle, apmd will log a
              warning  at  the ALERT log level to syslog(2) and generate a LOW
              BATTERY event.  If the -W or --wall option was given, the daemon
              will also use wall(1) to alert all users of impending doom.  The
              default warning level is 10.  Use a negative  value  to  disable
              this feature.

       -h, --help
              Causes apmd to print a brief command summary and exit.

BUGS

       This  daemon  supports  all  APM  events  described  in  the  APM  BIOS
       specification version 1.2; however it fails  to  support  some  of  the
       advanced  features  of  APM  1.2,  such  as reporting the conditions of
       multiple batteries.  (Multiple batteries are currently  treated  as  if
       they were just one large one.)

       Estimates  of  charge  and  discharge  rates  and  times  can  be  very
       inaccurate.

       There is no interaction yet with ACPI support  as  found  in  newer  PC
       hardware.

FILES

       /dev/apm_bios
              Device  through  which  apmd  communicates  with  the  Linux APM
              driver.

       /proc/apm
              APM driver status information

       /etc/apmd_proxy
              Proxy program that is run if none is specified.

       /etc/apm/apmd_proxy
              Proxy program that is run if none is specified. (Debian)

AUTHOR

       This program was written by Rik Faith  (faith@cs.unc.edu)  and  may  be
       freely  distributed  under the terms of the GNU General Public License.
       There  is  ABSOLUTELY  NO  WARRANTY  for  this  program.   The  current
       maintainer is Avery Pennarun (apenwarr@worldvisions.ca).

SEE ALSO

       apm(1), xapm(1), cardctl(8), syslogd(8).

                                 January 2004                          APMD(8)