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.Dd March 21, 2021
.Dt AUDIOCTL 1
.Os
.Sh NAME
.Nm audioctl
.Nd control software audio format
.Sh SYNOPSIS
.Nm
.Op Fl n
.Op Fl d Ar device
.Fl a
.Nm
.Op Fl n
.Op Fl d Ar device
.Ar name ...
.Nm
.Op Fl n
.Op Fl d Ar device
.Fl w
.Ar name=value ...
.Sh DESCRIPTION
The
.Nm
command displays or sets the parameters that determine the playback and
recording format for software using an audio device.
It is most useful when the full
.Xr audio 4
API is not available, e.g. when playing or recording raw audio data from a
.Xr sh 1
script, or from the command line.
It does not control the underlying hardware format, which can be
changed with
.Xr audiocfg 1 .
.Pp
The variables that can be inspected and changed with
.Nm
are normally per-application and are reset when a
.Pa /dev/audioX
device is opened.
This can be circumvented by using
.Pa /dev/soundX
instead, which retains global state.
.Pp
If a list of variables is present on the command line, then
.Nm
prints the current value of those variables for the specified device.
If the
.Fl a
flag is specified, all variables for the device are printed.
If the
.Fl w
flag is specified
.Nm
attempts to set the specified variables to the given values.
.Pp
The
.Fl d
flag can be used to give an alternative audio control device, the default is
.Pa /dev/audioctl0 .
.Pp
The
.Fl n
flag suppresses printing of the variable name.
.Sh ENVIRONMENT
.Bl -tag -width AUDIOCTLDEVICE
.It Pa AUDIOCTLDEVICE
the audio control device to use.
.El
.Sh FILES
.Bl -tag -width /dev/audioctl0 -compact
.It Pa /dev/sound0
audio I/O device
.It Pa /dev/audioctl0
audio control device
.El
.Sh EXAMPLES
To set the playing sampling rate to 11025, you can use
.Dl audioctl -w play.sample_rate=11025
To set all of the play parameters for CD-quality audio, you can use
.Dl audioctl -w play=44100,2,16,slinear_le
.Sh COMPATIBILITY
The old
.Fl f
flag is still supported.
This support will be removed eventually.
.Sh SEE ALSO
.Xr audiocfg 1 ,
.Xr audioplay 1 ,
.Xr audiorecord 1 ,
.Xr mixerctl 1 ,
.Xr audio 4 ,
.Xr sysctl 8
.Sh HISTORY
The
.Nm
command first appeared in
.Nx 1.3 .
.Sh CAVEATS
Since the parameters controlled by
.Nm
are global, they can be changed unexpectedly if another application
uses the same audio device.
.Pp
It is always preferable to use
.Dv AUDIO_SETINFO
on a per-process
.Pa /dev/audioX
device, if the
.Xr audio 4
ioctls are available in the programming environment.
Similarly,
.Xr audioplay 1
and
.Xr audiorecord 1
are more safe for use in scripting.