NAME

apmd — Advanced Power Management monitor daemon

SYNOPSIS

DESCRIPTION

The apmd utility monitors the occurrence of the specified Advanced Power Management (APM) events and, if one of the events occurs, it executes the sequence of commands corresponding to the event. Only the events specified in the configuration file are notified to apmd; all other events are ignored. For each event posted by the APM BIOS, apmd invokes the sequence of commands specified in the configuration file. When apmd is running with monitoring suspend/standby requests, the kernel will not process those requests. Therefore, if you wish action to be taken when these events occur, you need to explicitly configure the appropriate commands or built-in functions in the configuration file.

The apmd utility recognizes the following runtime options:

-d

Starts in debug mode. This causes apmd to execute in the foreground instead of in daemon mode.

-f file

Specifies a different configuration file file to be used in place of the default /etc/apmd.conf.

-s

Causes apmd to simulate a POWERSTATECHANGE event when a power state change is detected (AC_POWER_STATE) but the bios of the laptop does not report it. This enables you to do things like dimming the LCD backlight when you unplug the power cord.

-v

Verbose mode.

When apmd starts, it reads the configuration file (/etc/apmd.conf as default) and notifies the set of events to be monitored to the APM device driver. When it terminates, the APM device driver automatically cancels monitored events.

If the apmd process receives a SIGHUP, it will reread its configuration file and notify the APM device driver of any changes to its configuration.

The apmd utility uses the device /dev/apmctl to issue ioctl(2) requests for monitoring events and for controlling the APM system. This device file is opened exclusively, so only a single apmd process can be running at any time.

When apmd receives an APM event, it forks a child process to execute the commands specified in the configuration file and then continues listening for more events. The child process executes the commands specified, one at a time and in the order that they are listed.

While apmd is processing the command list for SUSPEND/STANDBY requests, the APM kernel device driver issues notifications to APM BIOS once per second so that the BIOS knows that there are still some commands pending, and that it should not complete the request just yet.

The apmd utility creates the file /var/run/apmd.pid, and stores its process id there. This can be used to kill or reconfigure apmd.

CONFIGURATION FILE

The structure of the apmd configuration file is quite simple. For example:

apm_event SUSPENDREQ {
       exec "sync && sync && sync";
       exec "sleep 1";
       exec "zzz";
}

will cause apmd to receive the APM event ‘SUSPENDREQ’ (which may be posted by an LCD close), run the ‘sync’ command 3 times and wait for a while, then execute zzz (apm -z) to put the system in the suspend state.

• The apm_event keyword
  ‘apm_event’ is the keyword which indicates the start of configuration for each event.
• APM events
  If you wish to execute the same commands for different events, the event names should be delimited by a comma. The following are valid event names:

  • - Events ignored by the kernel if apmd is running:

    STANDBYREQ

     

    USERSTANDBYREQ

     

    SUSPENDREQ

    should include sync in the command list,

    USERSUSPENDREQ

    should include sync in the command list,

    BATTERYLOW

    only zzz should be specified in the command list.

  • - Events passed to apmd after kernel handling:

    NORMRESUME

     

    CRITRESUME

     

    STANDBYRESUME

     

    POWERSTATECHANGE

     

    UPDATETIME

     

    CAPABILITIESCHANGE

     

    Other events will not be sent to apmd.

• command line syntax
  In the example above, the three lines beginning with ‘exec’ are commands for the event. Each line should be terminated with a semicolon. The command list for the event should be enclosed by ‘{’ and ‘}’. The apmd utility uses /bin/sh for double-quotation enclosed command execution, just as with system(3). Each command is executed in order until the end of the list is reached or a command finishes with a non-zero status code. The apmd utility will report any failed command's status code via syslog(3) and will then reject the request event posted by the APM BIOS.
• Built-in functions
  You can also specify apmd built-in functions instead of command lines. A built-in function name should be terminated with a semicolon, just as with a command line. The following built-in functions are currently supported:

  • - reject

    Reject last request posted by APM BIOS. This can be used to reject a SUSPEND request when the LCD is closed and put the system in a STANDBY state instead.

FILES

/etc/apmd.conf

 

/dev/apmctl

 

/var/run/apmd.pid

 

EXAMPLES

Sample configuration commands include:

apm_event SUSPENDREQ {
        exec "/etc/rc.suspend apm suspend";
}

apm_event USERSUSPENDREQ {
        exec "sync && sync && sync";
        exec "sleep 1";
        exec "apm -z";
}

apm_event NORMRESUME {
        exec "/etc/rc.resume apm suspend";
}

apm_event STANDBYRESUME {
        exec "/etc/rc.resume apm standby";
}

# resume event configuration for serial mouse users by
# reinitializing a moused(8) connected to a serial port.
#
#apm_event NORMRESUME {
#       exec "kill -HUP `cat /var/run/moused.pid`";
#}
#
# suspend request event configuration for ATA HDD users:
# execute standby instead of suspend.
#
#apm_event SUSPENDREQ {
#       reject;
#       exec "sync && sync && sync";
#       exec "sleep 1";
#       exec "apm -Z";
#}

SEE ALSO

apm(4), apm(8)

HISTORY

The apmd utility appeared in FreeBSD 3.3.

AUTHORS

Mitsuru IWASAKI <iwasaki@FreeBSD.org>
KOIE Hidetaka <koie@suri.co.jp>

Some contributions made by Warner Losh <imp@FreeBSD.org>, Hiroshi Yamashita <bluemoon@msj.biglobe.ne.jp>, Yoshihiko SARUMARU <mistral@imasy.or.jp>, Norihiro Kumagai <kuma@nk.rim.or.jp>, NAKAGAWA Yoshihisa <nakagawa@jp.FreeBSD.org>, and Nick Hilliard <nick@foobar.org>.