NAME

mixerctl — control audio mixing

SYNOPSIS

DESCRIPTION

The mixerctl command displays or sets various audio system mixing variables. If a list of variables is present on the command line, mixerctl prints the current value of those variables for the specified device. Variables can also be set at system startup using the configuration file mixerctl.conf(5).

The options are as follows:

-a

Print all device variables and their current values. This is the default, if no parameters are given to mixerctl.

-f file

Specify an alternative audio mixing device. The default is /dev/mixer0.

-n

Suppress printing of the variable name.

-q

Suppress all printing when setting a variable.

-t

Toggle. Attempt to select the next possible value of an enum (see below).

-v

Show all possible values of variables. Enum values are shown in ‘[]’ and values belonging to a set are shown in ‘{}’ (see below).

name=value

Attempt to set the specified variable name to value.

The exact set of controls that can be manipulated depends on the mixer. The general format (in both getting and setting a value) is:

The class can have values like “inputs” or “outputs”, indicating that the control affects the input or output, respectively, to the mixer. The name indicates what part of the mixer the control affects. Continuous mixer values, e.g. volume, have numeric values in the range 0-255. If value can be set for each channel independently, the values are printed separated by commas. Discrete mixer values, e.g. the recording source, have symbolic names.

Variables may take one of three types, again dependent on the mixer:

1. Enums. These may take only one out of a possible list of symbolic values or the literal string “toggle”, which toggles the value, e.g. inputs.mic.source=mic0.
2. Sets. These can take one or more of a possible list of symbolic values; multiple values are specified as a comma-separated list, e.g. record.source=mic,cd. Additionally, value may be omitted to specify the empty set, e.g. record.source=.
3. Numbers. Numerical values may be specified in either absolute or relative forms. The relative form is indicated by a prefix of ‘+’ or ‘-’ to denote an increase or decrease, respectively.

ENVIRONMENT

MIXERDEVICE

The audio mixer device to use.

FILES

/dev/mixer0

Default mixer audio device.

/etc/mixerctl.conf

mixerctl configuration file.

EXAMPLES

Show possible values for all mixer variables, and their current settings:

$ mixerctl -av
inputs.mic=0,0 volume
inputs.mic.mute=off  [ off on ]
inputs.cd=220,220 volume
inputs.cd.mute=off  [ off on ]
inputs.dac=220,220 volume
inputs.dac.mute=off  [ off on ]
record.record=220,220 volume
record.record.source=mic  [ mic cd dac ]
monitor.monitor=0 volume

Toggle inputs.dac.mute:

$ mixerctl -t inputs.dac.mute
inputs.dac.mute: off -> on
$ mixerctl inputs.dac.mute=toggle
inputs.dac.mute: on -> off

SEE ALSO

aucat(1), audioctl(1), cdio(1), audio(4), mixerctl.conf(5), sysctl(8)

HISTORY

The mixerctl command first appeared in OpenBSD 2.4.