APMD

Section: Linux Programmer's Manual (8)
Updated: 10 Jan 1996
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Copyright 1996 Rickard E. Faith (mailto:r.faith@ieee.org)

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NAME

apmd - Advanced Power Management (APM) BIOS daemon

SYNOPSIS

apmd [ -vVW ] [ -p percent_change ] [ -w warn_percent ]

DESCRIPTION

apmd is an APM BIOS monitoring daemon. It will log, via syslogd(2), changes in APM power status (e.g., on or off AC power, discharging or charging battery). When the available battery power becomes very low, it can use wall(1) to alert all users on the system. When the APM BIOS notifies the daemon of a pending suspend or standby request, apmd will call sync(2), sleep for 2 seconds, and then tell the APM BIOS to continue its operation. When a critical resume occurs, apmd will make a feable attempt to reset the clock.

The information logged contains 4 fields:

: 1) Rate of discharge (percent/minute). Negative rates indicate charging.
: 2) Time since total charge or total discharge (hh:mm:ss). This value is only useful if it reflects the time since a 100% or 0% state has been reached. Otherwise, this time is in parentheses, and reflects the time since the last important apmd status change.
: 3) Estimate of time left until total discharge (or total charge), assuming use similar to that since the last resume ( or since AC was connected). This time is calculated by apmd itself.
: 4) Parenthetically, the percent and length of remaining battery life, as estimated by the APM BIOS (which is often an estimate from the intelligent battery itself).

OPTIONS

-V, --version: Print version and exit.
-v, --verbose: Log all APM events
-p percent_change, --percentage percent_change: Every time the percentage of available power changes by percent_change, log information. The default is 5. Use values greater than 100 to disable this feature.
-w warn_percent, --warn warn_percent: When the battery is not being charged and the percentage of available power drops below warn_percent, log a warning at ALERT level to syslog(2). If the -W or --wall flag was given, use wall(1) to alert all users of impending doom. Give the warning each time the percentage changes. The default is 10. Use negative values to disable this feature.
-W, --wall: In addition to logging via syslog(2), 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 noise will be made during the critical time period.

BUGS

The first status report printed after a power change may be inaccurate because the power change occured at a fractional percentage that was rounded to a full percentage. For example, say you are discharging the machine and have 50.9% power, which is reported as 50%. When you start to charge the machine, it will only have 0.1% left before the percentage flips to 50%, and the charge rate will be dramatically over-estimated.

FILES

/proc/apm
/proc/devices

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 WARANTY for this program.

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