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snd_ctl_mixer_switch_write()

Adjust a mixer switch setting

Synopsis:

#include  < sys/asoundlib.h > 

int snd_ctl_mixer_switch_write(
       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_write() writes to the driver about the switch.

Library:

libasound.so

Description:

The snd_ctl_mixer_switch_write() function writes the snd_switch_t structure for the switch identified by the structure's name member.

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

Caveats:

The switch struct must be initialized completely before making the call.

See also:

snd_mixer_group_write(), mix_ctl.c application example source code


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