snd_ctl_mixer_switch_read()
Get a mixer switch setting
Synopsis:
#include <sys/asoundlib.h >
int snd_ctl_mixer_switch_read(
snd_ctl_t *handle,
int dev,
snd_switch_t * sw )
Arguments:
- handle
- The handle for the control device. This must have been created by snd_ctl_open() .
- dev
- The mixer device the switches apply to.
- sw
- A pointer to a snd_switch_t structure that snd_ctl_mixer_switch_read() fills with information about the switch.
Library:
libasound.so
Use the -l asound option to qcc to link against this library.
Description:
The snd_ctl_mixer_switch_read() function reads the snd_switch_t structure for the switch identified by the name member of the structure.
You must initialize the name member before calling this function.
Returns:
Zero on success, or a negative value if an error occurs.
Errors:
- -EINVAL
- Invalid handle argument.
- -ENXIO
- The group wasn't found.
Classification:
QNX Neutrino
| Safety: | |
|---|---|
| Cancellation point | No |
| Interrupt handler | No |
| Signal handler | Yes |
| Thread | Yes |