APMD(8)

APMD(8) | System Manager's Manual | APMD(8)

# NAME

`apmd` — Advanced Power Management monitor daemon

# SYNOPSIS

`apmd` | [`-adlqsv`] [`-f` devname] [`-m` sockmode] [`-o` sockowner:sockgroup] [`-S` sockname] [`-t` rate]

# DESCRIPTION

The `apmd` daemon monitors the Advanced Power Management (APM) pseudo-device, acting on signaled events and upon user requests as sent by the apm(8) utility. The `apmd` daemon is only installed on supported platforms.

The `apmd` is largely deprecated. Modern systems supporting ACPI should rely on acpi(4), powerd(8), and the envsys(4) framework instead.

For suspend and standby request events delivered by the BIOS, or via apm(8), `apmd` runs the appropriate configuration program (if one exists), syncs the buffer cache to disk and initiates the requested mode. When resuming after suspend or standby, `apmd` runs the appropriate configuration utility (if one exists). For power status change events, `apmd` fetches the current status and reports it via syslog(3) with logging facility `LOG_DAEMON`.

`apmd` announces the transition to standby mode with a single high tone on the speaker (using the /dev/speaker device). Suspends are announced with two high tones.

`apmd` periodically polls the APM driver for the current power state. If the battery charge level changes substantially or the external power status changes, the new status is logged. The polling rate defaults to once per 10 minutes, but this may be altered by using the `-t` command-line flag.

`apmd` supports the following options:

`-a`
  Any BIOS-initiated suspend or standby requests are ignored if the system is connected to line current and not running from batteries (user requests are still honored).
`-d`
  Enter debug mode, log to facility `LOG_LOCAL1` and stay in the foreground on the controlling terminal.
`-f` devname
  Specify an alternate device file name.
`-l`
  A low-battery event causes a suspend request to occur.
`-m` sockmode
  Use sockmode instead of ‘0660’ for the mode of /var/run/apmdev.
`-o` sockowner:sockgroup
  Use sockowner:sockgroup instead of ‘`0:0'’ for the owner/group of /var/run/apmdev.
`-q`
  Do not announce suspend and standby requests on the speaker.
`-S` sockname
  Specify an alternate socket name (used by apm(8) to communicate with `apmd`).
`-s`
  The current battery statistics are reported via syslog(3) and exit without monitoring the APM status.
`-t` rate
  Change the polling rate from 600 seconds to rate seconds.
`-v`
  Periodically log the power status via syslog(3).

When a client requests a suspend or stand-by mode, `apmd` does not wait for positive confirmation that the requested mode has been entered before replying to the client; to do so would mean the client does not get a reply until the system resumes from its sleep state. Rather, `apmd` replies with the intended state to the client and then places the system in the requested mode after running the configuration script and flushing the buffer cache.

Actions can be configured for the five transitions: `suspend`, `standby`, `resume`, `line` or `battery`. The suspend and standby actions are run prior to `apmd` performing any other actions (such as disk syncs) and entering the new mode. The resume program is run after resuming from a stand-by or suspended state.

The line and battery actions are run after switching power sources to AC (line) or battery, respectively. The appropriate line or battery action is also run upon the startup of apmd based on the current power source.

# FILES

/etc/apm/suspend
/etc/apm/standby
/etc/apm/resume
/etc/apm/line
/etc/apm/battery
  Contain the host's customized actions. Each file must be an executable binary or shell script suitable for execution by the execve(2) function. If you wish to have the same program or script control all transitions, it may determine which transition is in progress by examining its argv[0] which is set to one of suspend, standby, resume, line or battery. See /usr/share/examples/apm/script for such an example script.

/var/run/apmdev
  The default UNIX-domain socket used for communication with apm(8). The socket is protected by default to mode 0660, UID 0, GID 0.

/dev/apmctl
  The default device used to control the APM kernel driver.

# SEE ALSO

execve(2), syslog(3), apm(4), speaker(4), apm(8), syslogd(8)

# HISTORY

The `apmd` daemon appeared in NetBSD 1.3.

March 20, 2010 | NetBSD 11.0