ALSACTL 1 "07 May 2014"
NAME
alsactl - advanced controls for ALSA soundcard driver
SYNOPSIS
alsactl [
options] [
store|
restore|
init] <card # or id or device>
alsactl monitor <card # or id>
alsactl [
clean] <card # or id or device> [[control identifiers]]
DESCRIPTION
alsactl is used to control advanced settings for the ALSA
soundcard drivers. It supports multiple soundcards. If your card has
features that you can't seem to control from a mixer application,
you have come to the right place.
COMMANDS
Introduction
The
<card> argument is optional. If no soundcards are specified,
setup for all cards will be saved, loaded or monitored.
store <card>
This command saves the current driver state for the selected soundcard
to the configuration file.
restore <card>
This command loads driver state for the selected soundcard from the
configuration file. If restoring fails (eventually partly), the init
action is called.
nrestore <card>
This command is like
restore, but it notifies also the daemon
to do new rescan for available soundcards.
init <card>
This command tries to initialize all devices to a default state. If device
is not known, error code 99 is returned.
daemon
This command manages to save periodically the sound state.
rdaemon
This command is like
daemon but restore the sound state at first.
kill <cmd>
This command notifies the daemon to do the specified operation (quit,
rescan, save_and_quit).
monitor <card>
This command is for monitoring the events received from the given
control device.
clean <card> [filter]
This command cleans the controls created by applications.
The optional element identifiers are accepted as a filter. One extra
argument is parsed as an element identifiers.
Example: alsactl clean 0 "name='PCM'" "name='Mic Phantom'"
dump-state
This command dumps the current state (all cards) to stdout.
dump-cfg
This command dumps the current configuration (all cards) to stdout.
Note that the configuration hooks are evaluated.
OPTIONS
-h, --help
Help: show available flags and commands.
-d, --debug
Use debug mode: a bit more verbose.
-v, --version
Print alsactl version number.
-f, --file
Select the configuration file to use. The default is /var/lib/alsa/asound.state.
-a, --config-dir
Select the boot / hotplug ALSA configuration directory to use. The default is /var/lib/alsa.
-l, --lock
Use the file locking to serialize the concurrent access to the state file (this
option is default for the global state file).
-L, --no-lock
Do not use the file locking to serialize the concurrent access to the state
file (including the global state file).
-O, --lock-state-file
Select the state lock file path.
-F, --force
Used with restore command. Try to restore the matching control elements
as much as possible. This option is set as default now.
-g, --ignore
Used with store, restore and init commands. Do not show 'No soundcards found'
and do not set an error exit code when soundcards are not installed.
-P, --pedantic
Used with restore command. Don't restore mismatching control elements.
This option was the old default behavior.
-I, --no-init-fallback
Don't initialize cards if restore fails. Since version 1.0.18,
alsactl tries to initialize the card with the restore operation
as default. But this can cause incompatibility with the older version.
The caller may expect that the state won't be touched if no state file
exists. This option takes the restore behavior back to the older
version by suppressing the initialization.
-r, --runstate
Save restore and init state to this file. The file will contain only errors.
Errors are appended with the soundcard id to the end of file.
-R, --remove
Remove runstate file at first.
-E, --env #=#
Set environment variable (useful for init action or you may override
ALSA_CONFIG_PATH to read different or optimized configuration - may be
useful for "boot" scripts).
-i, --initfile
The configuration file for init. By default, PREFIX/share/alsa/init/00main
is used.
-p, --period
The store period in seconds for the daemon command.
-e, --pid-file
The pathname to store the process-id file in the HDB UUCP format (ASCII).
-b, --background
Run the task in background.
-s, --syslog
Use syslog for messages.
-n, --nice
Set the process priority (see 'man nice')
-c, --sched-idle
Set the process scheduling policy to idle (SCHED_IDLE).
-D, --ucm-defaults
Execute also the 'defaults' section from the UCM configuration. The standard
behaviour is to execute only 'once' section.
-U, --no-ucm
Skip the UCM init even if available. It may be useful for the test the
legacy init configuration.
FILES
/var/lib/alsa/asound.state (or whatever file you specify with the
-f flag) is used to store current settings for your
soundcards. The settings include all the usual soundcard mixer
settings. More importantly, alsactl is
capable of controlling other card-specific features that mixer apps
usually don't know about.
The configuration file is generated automatically by running
alsactl store. Editing the configuration file by hand may be
necessary for some soundcard features (e.g.
enabling/
disabling
automatic mic gain, digital output,
joystick/
game ports, some future MIDI
routing options, etc).
SEE ALSO
amixer(1),
alsamixer(1),
aplay(1),
alsactl_init(7)
BUGS
None known.
AUTHOR
alsactl is by Jaroslav Kysela <perex@perex.cz> and Abramo Bagnara
<abramo@alsa-project.org>. This document is by Paul Winkler <zarmzarm@erols.com>.