AUDIOCTL(1) | General Commands Manual | AUDIOCTL(1) |
audioctl
—
audioctl |
[-n ] [-d
device] -a |
audioctl |
[-n ] [-d
device] name ... |
audioctl |
[-n ] [-d
device] -w
name=value ... |
audioctl
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
audio(4) API is not available,
e.g. when playing or recording raw audio data from a
sh(1) script, or from the command
line. It does not control the underlying hardware format, which can be changed
with audiocfg(1).
The variables that can be inspected and changed with
audioctl
are normally per-application and are reset
when a /dev/audioX device is opened. This can be
circumvented by using /dev/soundX instead, which
retains global state.
If a list of variables is present on the command line, then
audioctl
prints the current value of those variables
for the specified device. If the -a
flag is
specified, all variables for the device are printed. If the
-w
flag is specified
audioctl
attempts to set the specified variables to
the given values.
The -d
flag can be used to give an
alternative audio control device, the default is
/dev/audioctl0.
The -n
flag suppresses printing of the
variable name.
audioctl -w
play.sample_rate=11025
audioctl -w
play=44100,2,16,slinear_le
-f
flag is still supported. This support will be
removed eventually.
audioctl
command first appeared in
NetBSD 1.3.
audioctl
are global,
they can be changed unexpectedly if another application uses the same audio
device.
It is always preferable to use
AUDIO_SETINFO
on a per-process
/dev/audioX device, if the
audio(4) ioctls are available
in the programming environment. Similarly,
audioplay(1) and
audiorecord(1) are more
safe for use in scripting.
March 21, 2021 | NetBSD 9.4 |