Computer Science
APMD(8) Linux Programmer's Manual APMD(8)
NAME
apmd - Advanced Power Management (APM) BIOS daemon
SYNOPSIS
apmd [ -vVuW ] [ -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. Other-
wise, 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
-u, --utc
BIOS clock is set to UTC (GMT), so pass -u option
to clock or hwclock program when coming out of sus-
pend mode.
-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 dis-
able this feature.
-w warn_percent, --warn warn_percent
When the battery is not being charged and the per-
centage of available power drops below warn_per-
cent, 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 warn-
ing each time the percentage changes. The default
is 10. Use negative values to disable this fea-
ture.
-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 frac-
tional 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 51%, and the charge rate will be dra-
matically 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 WARRANTY
for this program. The current maintainer is Avery Pen-
narun (apenwarr@worldvisions.ca).
SEE ALSO
apm(1), xapmd(1)
10 Jan 1996 1
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