snd_mixer_file_descriptor()

Return the file descriptor of the connection to the sound mixer interface

Synopsis:

#include <sys/asoundlib.h>

int snd_mixer_file_descriptor(
       snd_mixer_t *handle );

Arguments:

handle
The handle for the mixer device. This must have been created by snd_mixer_open().

Library:

libasound.so

Use the -l asound option to qcc to link against this library.

Description:

The snd_mixer_file_descriptor() function returns the file descriptor of the connection to the sound mixer interface.

You should use this file descriptor with the select() synchronous multiplexer function (see the QNX Neutrino C Library Reference) to receive notification of mixer events. If data is waiting to be read, you can read in the events with snd_mixer_read().

Returns:

The file descriptor of the connection to the mixer interface on success, or a negative error code.

Errors:

-EINVAL
Invalid handle argument.

Classification:

QNX Neutrino

Safety:  
Cancellation point No
Interrupt handler No
Signal handler Yes
Thread Yes