:: RootR ::  Hosting Order Map Login   Secure Inter-Network Operations  
acpid(8) - phpMan

Command: man perldoc info search(apropos)  

acpid(8)                             System Manager's Manual                             acpid(8)

       acpid - Advanced Configuration and Power Interface event daemon

       acpid [options]

       acpid  is  designed to notify user-space programs of ACPI events.  acpid should be started
       during the system boot, and will run as a background process, by default.  It will open an
       events  file (/proc/acpi/event by default) and attempt to read whole lines which represent
       ACPI events.  If the events file does not exist, acpid will  attempt  to  connect  to  the
       Linux  kernel via the input layer and netlink.  When an ACPI event is received from one of
       these sources, acpid will examine a list of rules, and execute the rules  that  match  the
       event.  acpid  will ignore all incoming ACPI events if a lock file exists (/var/lock/acpid
       by default).

       Rules are defined by simple configuration files.   acpid  will  look  in  a  configuration
       directory  (/etc/acpi/events by default), and parse all regular files with names that con‐
       sist entirely of upper and lower case letters, digits, underscores, and  hyphens  (similar
       to  run-parts(8)).   Each  file must define two things: an event and an action.  Any blank
       lines, or lines where the first character is a hash ('#') are ignored.   Extraneous  lines
       are  flagged  as warnings, but are not fatal.  Each line has three tokens: the key, a lit‐
       eral equal sign, and the value.  The key can be up to 63 characters, and is  case-insensi‐
       tive  (but  whitespace  matters).   The value can be up to 511 characters, and is case and
       whitespace sensitive.

       The event value is a  regular  expression  (see  regcomp(3)),  against  which  events  are

       The  action  value  is  a commandline, which will be invoked via /bin/sh whenever an event
       matching the rule in question occurs.  The commandline may include  shell-special  charac‐
       ters,  and they will be preserved.  The only special characters in an action value are "%"
       escaped.  The string "%e" will be replaced by the literal text of the event for which  the
       action  was invoked.  This string may contain spaces, so the commandline must take care to
       quote the "%e" if it wants a single token.  The string "%%" will be replaced by a  literal
       "%".  All other "%" escapes are reserved, and will cause a rule to not load.

       This feature allows multiple rules to be defined for the same event (though no ordering is
       guaranteed), as well as one rule to be defined for multiple events.   To  force  acpid  to
       reload the rule configuration, send it a SIGHUP.

       The pseudo-action <drop> causes the event to be dropped completely and no further process‐
       ing undertaken; clients connecting via the UNIX domain socket  (see  below)  will  not  be
       notified  of the event. This may be useful on some machines, such as certain laptops which
       generate spurious battery events at frequent intervals. The name of this pseudo-action may
       be redefined with a commandline option.

       In  addition  to  rule  files,  acpid  also  accepts  connections  on a UNIX domain socket
       (/var/run/acpid.socket by default).  Any application may connect  to  this  socket.   Once
       connected,  acpid will send the text of all ACPI events to the client.  The client has the
       responsibility of filtering for messages about which it cares.  acpid will not  close  the
       client socket except in the case of a SIGHUP or acpid exiting.

       For  faster  startup,  this socket can be passed in as stdin so that acpid need not create
       the socket.  In addition, if a socket is passed in as stdin, acpid will not daemonize.  It
       will be run in foreground.  This behavior is provided to support systemd(1).

       acpid  will log all of its activities, as well as the stdout and stderr of any actions, to

       All the default files and directories can be changed with commandline options.

       -c, --confdir directory
                   This option changes the directory in which acpid looks for rule  configuration
                   files.  Default is /etc/acpi/events.

       -C, --clientmax number
                   This  option  changes  the maximum number of non-root socket connections which
                   can be made to the acpid socket.  Default is 256.

       -d, --debug This option increases the acpid debug level by one.  If  the  debug  level  is
                   non-zero,  acpid  will run in the foreground, and will log to stderr, in addi‐
                   tion to the regular syslog.

       -e, --eventfile filename
                   This option changes the event file from which acpid reads events.  Default  is

       -n, --netlink
                   This  option  forces  acpid  to  use  the Linux kernel input layer and netlink
                   interface for ACPI events.

       -f, --foreground
                   This option keeps acpid in the foreground by not forking at startup.

       -l, --logevents
                   This option tells acpid to log information about all events and actions.

       -L, --lockfile filename
                   This option changes the lock file used to stop event processing.   Default  is

       -g, --socketgroup groupname
                   This  option  changes  the  group ownership of the UNIX domain socket to which
                   acpid publishes events.

       -m, --socketmode mode
                   This option changes the permissions of the UNIX domain socket to  which  acpid
                   publishes events.  Default is 0666.

       -s, --socketfile filename
                   This  option  changes  the  name  of the UNIX domain socket which acpid opens.
                   Default is /var/run/acpid.socket.

       -S, --nosocket filename
                   This option tells acpid not to open a UNIX domain socket.  This overrides  the
                   -s option, and negates all other socket options.

       -p, --pidfile filename
                   This option tells acpid to use the specified file as its pidfile.  If the file
                   exists, it will be removed and over-written.  Default is /var/run/acpid.pid.

       -r, --dropaction action
                   This option defines the pseudo-action which tells acpid to abort all  process‐
                   ing of an event, including client notifications.  Default is <drop>.

       -t, --tpmutefix
                   This  option  enables special handling of the mute button for certain ThinkPad
                   models with mute LEDs that get out of sync with the mute state when  the  mute
                   button is held down.  With this option, the mute button will generate the fol‐
                   lowing events in sync with the number of presses (and, by extension, the state
                   of the LED):

                   button/mute MUTE (key pressed) K
                   button/mute MUTE (key released) K

       -v, --version
                   Print version information and exit.

       -h, --help  Show help and exit.

       This example will shut down your system if you press the power button.

       Create a file named /etc/acpi/events/power that contains the following:

              action=/etc/acpi/power.sh "%e"

       Then create a file named /etc/acpi/power.sh that contains the following:

              /sbin/shutdown -h now "Power button pressed"

       Now,  when  acpid  is  running,  a  press  of  the  power  button  will  cause the rule in
       /etc/acpi/events/power to trigger the script in /etc/acpi/power.sh.  The script will  then
       shut down the system.

       acpid  is  a  simple program that runs scripts in response to ACPI events from the kernel.
       When there's trouble, the problem is rarely with acpid itself.   The  following  are  some
       suggestions for finding the most common sources of ACPI-related problems.

       When troubleshooting acpid, it is important to be aware that other parts of a system might
       be handling ACPI events.  systemd(1) is capable of handling the power switch  and  various
       other events that are commonly handled by acpid.  See the description of HandlePowerKey in
       logind.conf(5) for more.  Some window managers also take over acpid's normal  handling  of
       the power button and other events.

       kacpimon(8)  can  be  used to verify that the expected ACPI events are coming in.  See the
       man page for kacpimon(8) for the proper procedure.  If the events aren't coming in, you've
       probably got a kernel driver issue.

       If  the  expected  events  are coming in, then you'll need to check and see if your window
       manager is responsible for handling these events.  Some are, some aren't.  (E.g. in Ubuntu
       14.04  (Unity/GNOME), there are settings for the laptop lid in the System Settings > Power
       > "When the lid is closed" fields.)  If your window manager is  responsible  for  handling
       the  problematic  event, and you've got it configured properly, then you may have a window
       manager issue.

       Lastly, take a look in /etc/acpi/events (see above).  Is there  a  configuration  file  in
       there  for  the  event in question (e.g. /etc/acpi/events/lidbtn for laptop lid open/close
       events)?  Is it properly connected to a script (e.g. /etc/acpi/lid.sh)?   Is  that  script
       working?   It's not unusual for an acpid script to check and see if there is a window man‐
       ager running, then do nothing if there is.  This means it is up to the window  manager  to
       handle this event.

       acpid should work on any linux kernel released since 2003.


       There are no known bugs.  To file bug reports, see PROJECT WEBSITE below.

       regcomp(3), sh(1), socket(2), connect(2), init(1), systemd(1), acpi_listen(8), kacpimon(8)


       Ted Felix <ted AT tedfelix.com>
       Tim Hockin <thockin AT hockin.org>
       Andrew Henroid


rootr.net - man pages