.B bind -a #A /dev
.sp 0.3v
.B /dev/audio
+.B /dev/audioctl
+.B /dev/audiostat
.B /dev/volume
.fi
.SH DESCRIPTION
.B audio
file as returned by
.IR stat (2)
-represents the number of bytes buffered for input or output.
+represents the number of bytes buffered for output.
+.PP
+.B Audioctl
+is driver specific control file and left undocumented here.
+.PP
+.B Audiostat
+is a read only status file. The first line has a length of 32 bytes
+including the newline and starts with the string
+.B bufsize
+followed by the prefered write unit (in bytes) and the string
+.B buffered
+followed by the number of bytes currently queued for output. The
+numbers are decimal and right-padded with spaces to fit.
+After this fixed header, the contents of the file is driver specific.
.PP
.B Volume
-is the control file associated with the audio port.
-Each input and output source has an associated stereo volume control,
-ranging from 0 (quiet) to 100 (loud).
-In addition, there are controls for the sampling rate of the D/A and A/D converters
+is the control file associated with the audio port. Each source has
+an associated stereo volume control,
+ranging from 0 (quiet) to 100 (loud).
+In addition, there are controls for the sampling rate,
latency control and for any tone controls.
Reads
return lines of the form
.IP
.I source
-.B in left
-.I value
-.B right
-.I value
-.B out left
-.I value
-.B right
+.I left
+.I right
+.PP
+or
+.IP
+.I source
.I value
.PP
-possibly abbreviated if the values are shared or non-existent.
-For example, if all of the values are shared, the form degenerates to
-.RI ` source
-.IR value '.
Valid sources depend on the particular audio device,
though all devices have an
.B audio
-stereo source, which controls the output volume from the D/A converter
-connected to
-.BR audio .
+stereo source, which controls the output volume from the D/A converter.
+Values for
+.B speed
+set the sampling frequency of the audio device and
+.B delay
+limits the audio data output buffering to a number of samples.
.PP
-Writes accept the same format with same abbreviations.
+Writes accept the same format except that for stereo sources
+.I left
+and
+.I right
+can be abbreviated to a single
+.I value
+if both should be set the same.
.SH SOURCE
.B /sys/src/9/port/devaudio.c
.SH SEE ALSO