.\"	$OpenBSD: apmd.8,v 1.42 2010/04/02 04:12:46 deraadt Exp $
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.\" Copyright (c) 1995 John T. Kohl
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.Dd $Mdocdate: April 2 2010 $
.Dt APMD 8
.Os
.Sh NAME
.Nm apmd
.Nd Advanced Power Management daemon
.Sh SYNOPSIS
.Nm apmd
.Op Fl AaCdHLs
.Op Fl f Ar devname
.Op Fl S Ar sockname
.Op Fl t Ar seconds
.Sh DESCRIPTION
.Nm
monitors the advanced power management device,
.Xr apm 4 ,
acting on signaled events and upon user requests as sent by the
.Xr apm 8
program.
.Pp
For suspend and standby request events delivered by the BIOS, or via
.Xr apm 8 ,
.Nm
runs the appropriate configuration program (if one exists),
syncs the buffer cache to disk and initiates the requested state.
When resuming after suspend or standby,
.Nm
runs the appropriate configuration program (if one exists).
.Pp
When the power status changes
(battery is connected or disconnected)
.Nm
fetches the current status and reports it via
.Xr syslog 3
with logging facility
.Dv LOG_DAEMON .
.Pp
The options are as follows:
.Bl -tag -width Ds
.It Fl A
Start
.Nm
in automatic performance adjustment mode.
In this mode, when CPU idle time falls below 10%,
or if the AC power is connected and the battery is more than 15% charged,
or if the battery is absent,
.Nm
raises
.Va hw.setperf
to 100.
Otherwise when CPU idle time is above 30%
and the system is running on battery power,
.Nm
lowers
.Va hw.setperf
as much as possible to reduce power consumption.
.It Fl a
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).
.It Fl C
Start
.Nm
in cool running performance adjustment mode.
In this mode, when CPU idle time falls below 10%,
.Nm
raises
.Va hw.setperf
as much as necessary.
Otherwise when CPU idle time is above 30%,
.Nm
lowers
.Va hw.setperf
as much as possible to reduce heat, noise, and power consumption.
.It Fl d
.Nm
enters debug mode, logging to facility
.Dv LOG_LOCAL1 ,
and stays in the foreground on the controlling terminal.
.It Fl f Ar devname
Specify an alternate device file name,
.Ar devname .
.It Fl H
Start
.Nm
in manual performance adjustment mode, initialising
.Va hw.setperf
to 100.
.It Fl L
Start
.Nm
in manual performance adjustment mode, initialising
.Va hw.setperf
to 0.
.It Fl S Ar sockname
Specify an alternate socket name,
.Ar sockname .
The socket is protected to mode 0660, UID 0, GID 0; this protects access
to suspend requests to authorized users only.
.It Fl s
Current battery statistics are reported via
.Xr syslog 3
and
.Nm
exits without monitoring the APM status.
.It Fl t Ar seconds
.Nm
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 may be specified using the
.Fl t
command-line flag.
.El
.Pp
When a client requests a suspend or stand-by state,
.Nm
does not wait for positive confirmation that the requested
state 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,
.Nm
replies with the intended state to the client and then places the system
in the requested state after running the configuration script and
flushing the buffer cache.
.Pp
Actions can be configured for the following five transitions:
suspend,
standby,
resume,
powerup,
and
powerdown.
The suspend and standby actions are run prior to
.Nm
performing any other actions (such as disk syncs) and entering the new
state.
The resume program is run after resuming from a stand-by or
suspended state.
The powerup and powerdown programs are run after the power status (AC
connected or not) changes, as well as after a resume (if the power
status changed in the mean time).
.Sh FILES
.Bl -tag -width "/etc/apm/powerdownXX" -compact
.It /dev/apmctl
Default device used to control the APM kernel driver.
.Pp
.It /etc/apm/suspend
.It /etc/apm/standby
.It /etc/apm/resume
.It /etc/apm/powerup
.It /etc/apm/powerdown
These files contain the host's customized actions.
Each file must be an executable binary or shell script.
A single program or script can be used to control all transitions
by examining its argument list,
which is set to one of
suspend,
standby,
resume,
powerup,
or
powerdown.
.Pp
.It /var/run/apmdev
Default
.Ux Ns -domain
socket used for communication with
.Xr apm 8 .
.El
.Sh SEE ALSO
.Xr syslog 3 ,
.Xr apm 4 ,
.Xr apm 8 ,
.Xr sysctl 8
.Pp
Advanced Power Management (APM) BIOS Interface Specification
(revision 1.2),
Intel Corporation and Microsoft Corporation.
.Sh HISTORY
The
.Nm
command first appeared in
.Nx 1.3 .
.Ox
support was added in
.Ox 1.2 .