snd_mixer_routes()

Get the number of routes in the mixer and their IDs

Synopsis:

#include <sys/asoundlib.h>

int snd_mixer_routes( snd_mixer_t *handle, 
                      snd_mixer_routes_t *routes );

Arguments:

handle

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

routes

A pointer to a snd_mixer_routes_t structure that snd_mixer_routes() fills in with information about the routes.

Library:

libasound.so

Description:

The snd_mixer_routes() function fills the given snd_mixer_routes_t structure with the number of routes in the mixer that the handle was opened on. It also fills in the array of route IDs pointed to by proutes to a limit of routes_size.

---

We recommend that you work with mixer groups instead of manipulating the elements directly.

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Before calling snd_mixer_routes(), set the members of this structure as follows:

proutes

This pointer must be NULL, or point to a valid storage location for the routes (i.e. an array of snd_mixer_eid_t structures).

routes_size

The size of this storage location in sizeof( snd_mixer_eid_t ) units (i.e. the number of entries in the proutes array).

On a successful return, the function sets these members:

routes

The total number of routes in the mixer.

routes_over

The number of routes that couldn't be copied to the storage location.

proutes

The list of routes.

Returns:

Zero on success, or a negative value on error.

Errors:

-EINVAL

Invalid handle.

Classification:

QNX Neutrino

See also:

snd_mixer_eid_t, snd_mixer_elements(), snd_mixer_groups(), snd_mixer_routes_t