ALSA project - the C library reference

Functions
mixer.c File Reference

Mixer Interface. More...

## Functions
int | snd_mixer_open (snd_mixer_t **mixerp, int mode)
| Opens an empty mixer. More...
int | snd_mixer_elem_attach (snd_mixer_elem_t *melem, snd_hctl_elem_t *helem)
| Attach an HCTL element to a mixer element. More...
int | snd_mixer_elem_detach (snd_mixer_elem_t *melem, snd_hctl_elem_t *helem)
| Detach an HCTL element from a mixer element. More...
int | snd_mixer_elem_empty (snd_mixer_elem_t *melem)
| Return true if a mixer element does not contain any HCTL elements. More...
int | snd_mixer_attach (snd_mixer_t *mixer, const char *name)
| Attach an HCTL specified with the CTL device name to an opened mixer. More...
int | snd_mixer_attach_hctl (snd_mixer_t *mixer, snd_hctl_t *hctl)
| Attach an HCTL to an opened mixer. More...
int | snd_mixer_detach (snd_mixer_t *mixer, const char *name)
| Detach a previously attached HCTL to an opened mixer freeing all related resources. More...
int | snd_mixer_detach_hctl (snd_mixer_t *mixer, snd_hctl_t *hctl)
| Detach a previously attached HCTL to an opened mixer freeing all related resources. More...
int | snd_mixer_get_hctl (snd_mixer_t *mixer, const char *name, snd_hctl_t **hctl)
| Obtain a HCTL pointer associated to given name. More...
void * | snd_mixer_elem_get_private (const snd_mixer_elem_t *elem)
| Get private data associated to give mixer element. More...
int | snd_mixer_elem_new (snd_mixer_elem_t **elem, snd_mixer_elem_type_t type, int compare_weight, void *private_data, void(*private_free)(snd_mixer_elem_t *elem))
| Allocate a new mixer element. More...
int | snd_mixer_elem_add (snd_mixer_elem_t *elem, snd_mixer_class_t *class)
| Add an element for a registered mixer element class. More...
int | snd_mixer_elem_remove (snd_mixer_elem_t *elem)
| Remove a mixer element. More...
void | snd_mixer_elem_free (snd_mixer_elem_t *elem)
| Free a mixer element. More...
int | snd_mixer_elem_info (snd_mixer_elem_t *elem)
| Mixer element informations are changed. More...
int | snd_mixer_elem_value (snd_mixer_elem_t *elem)
| Mixer element values is changed. More...
int | snd_mixer_class_register (snd_mixer_class_t *class, snd_mixer_t *mixer)
| Register mixer element class. More...
int | snd_mixer_class_unregister (snd_mixer_class_t *class)
| Unregister mixer element class and remove all its elements. More...
int | snd_mixer_load (snd_mixer_t *mixer)
| Load a mixer elements. More...
void | snd_mixer_free (snd_mixer_t *mixer)
| Unload all mixer elements and free all related resources. More...
int | snd_mixer_close (snd_mixer_t *mixer)
| Close a mixer and free all related resources. More...
int | snd_mixer_set_compare (snd_mixer_t *mixer, snd_mixer_compare_t compare)
| Change mixer compare function and reorder elements. More...
int | snd_mixer_poll_descriptors_count (snd_mixer_t *mixer)
| get count of poll descriptors for mixer handle More...
int | snd_mixer_poll_descriptors (snd_mixer_t *mixer, struct pollfd *pfds, unsigned int space)
| get poll descriptors More...
int | snd_mixer_poll_descriptors_revents (snd_mixer_t *mixer, struct pollfd *pfds, unsigned int nfds, unsigned short *revents)
| get returned events from poll descriptors More...
int | snd_mixer_wait (snd_mixer_t *mixer, int timeout)
| Wait for a mixer to become ready (i.e. at least one event pending) More...
snd_mixer_elem_t * | snd_mixer_first_elem (snd_mixer_t *mixer)
| get first element for a mixer More...
snd_mixer_elem_t * | snd_mixer_last_elem (snd_mixer_t *mixer)
| get last element for a mixer More...
snd_mixer_elem_t * | snd_mixer_elem_next (snd_mixer_elem_t *elem)
| get next mixer element More...
snd_mixer_elem_t * | snd_mixer_elem_prev (snd_mixer_elem_t *elem)
| get previous mixer element More...
int | snd_mixer_handle_events (snd_mixer_t *mixer)
| Handle pending mixer events invoking callbacks. More...
void | snd_mixer_set_callback (snd_mixer_t *obj, snd_mixer_callback_t val)
| Set callback function for a mixer. More...
void | snd_mixer_set_callback_private (snd_mixer_t *mixer, void *val)
| Set callback private value for a mixer. More...
void * | snd_mixer_get_callback_private (const snd_mixer_t *mixer)
| Get callback private value for a mixer. More...
unsigned int | snd_mixer_get_count (const snd_mixer_t *mixer)
| Get elements count for a mixer. More...
void | snd_mixer_elem_set_callback (snd_mixer_elem_t *mixer, snd_mixer_elem_callback_t val)
| Set callback function for a mixer element. More...
void | snd_mixer_elem_set_callback_private (snd_mixer_elem_t *mixer, void *val)
| Set callback private value for a mixer element. More...
void * | snd_mixer_elem_get_callback_private (const snd_mixer_elem_t *mixer)
| Get callback private value for a mixer element. More...
snd_mixer_elem_type_t | snd_mixer_elem_get_type (const snd_mixer_elem_t *mixer)
| Get type for a mixer element. More...
size_t | snd_mixer_class_sizeof ()
| get size of snd_mixer_class_t More...
int | snd_mixer_class_malloc (snd_mixer_class_t **ptr)
| allocate an invalid snd_mixer_class_t using standard malloc More...
void | snd_mixer_class_free (snd_mixer_class_t *obj)
| frees a previously allocated snd_mixer_class_t More...
void | snd_mixer_class_copy (snd_mixer_class_t *dst, const snd_mixer_class_t *src)
| copy one snd_mixer_class_t to another More...
snd_mixer_t * | snd_mixer_class_get_mixer (const snd_mixer_class_t *obj)
| Get a mixer associated to given mixer class. More...
snd_mixer_event_t | snd_mixer_class_get_event (const snd_mixer_class_t *obj)
| Get mixer event callback associated to given mixer class. More...
void * | snd_mixer_class_get_private (const snd_mixer_class_t *obj)
| Get mixer private data associated to given mixer class. More...
snd_mixer_compare_t | snd_mixer_class_get_compare (const snd_mixer_class_t *obj)
| Get mixer compare callback associated to given mixer class. More...
int | snd_mixer_class_set_event (snd_mixer_class_t *obj, snd_mixer_event_t event)
| Set mixer event callback to given mixer class. More...
int | snd_mixer_class_set_private (snd_mixer_class_t *obj, void *private_data)
| Set mixer private data to given mixer class. More...
int | snd_mixer_class_set_private_free (snd_mixer_class_t *obj, void(*private_free)(snd_mixer_class_t *))
| Set mixer private data free callback to given mixer class. More...
int | snd_mixer_class_set_compare (snd_mixer_class_t *obj, snd_mixer_compare_t compare)
| Set mixer compare callback to given mixer class. More...

## Detailed Description

Mixer Interface.

Author
  Jaroslav Kysela perex.nosp@m.@per.nosp@m.ex.cz
  Abramo Bagnara abram.nosp@m.o@al.nosp@m.sa-pr.nosp@m.ojec.nosp@m.t.org

Date
  2001

Mixer interface is designed to access mixer elements. Callbacks may be used for event handling.