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    ALSA project - the C library reference
    
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Data Fields | |
| snd_pcm_sframes_t(* | transfer )(snd_pcm_extplug_t *ext, const snd_pcm_channel_area_t *dst_areas, snd_pcm_uframes_t dst_offset, const snd_pcm_channel_area_t *src_areas, snd_pcm_uframes_t src_offset, snd_pcm_uframes_t size) | 
| int(* | close )(snd_pcm_extplug_t *ext) | 
| int(* | hw_params )(snd_pcm_extplug_t *ext, snd_pcm_hw_params_t *params) | 
| int(* | hw_free )(snd_pcm_extplug_t *ext) | 
| void(* | dump )(snd_pcm_extplug_t *ext, snd_output_t *out) | 
| int(* | init )(snd_pcm_extplug_t *ext) | 
| snd_pcm_chmap_query_t **(* | query_chmaps )(snd_pcm_extplug_t *ext) | 
| snd_pcm_chmap_t *(* | get_chmap )(snd_pcm_extplug_t *ext) | 
| int(* | set_chmap )(snd_pcm_extplug_t *ext, const snd_pcm_chmap_t *map) | 
Callback table of extplug
| int(* snd_pcm_extplug_callback_t::close) (snd_pcm_extplug_t *ext) | 
close the PCM; optional
| void(* snd_pcm_extplug_callback_t::dump) (snd_pcm_extplug_t *ext, snd_output_t *out) | 
dump; optional
| snd_pcm_chmap_t*(* snd_pcm_extplug_callback_t::get_chmap) (snd_pcm_extplug_t *ext) | 
get the channel map; optional; since v1.0.2
| int(* snd_pcm_extplug_callback_t::hw_free) (snd_pcm_extplug_t *ext) | 
hw_free; optional
| int(* snd_pcm_extplug_callback_t::hw_params) (snd_pcm_extplug_t *ext, snd_pcm_hw_params_t *params) | 
hw_params; optional
| int(* snd_pcm_extplug_callback_t::init) (snd_pcm_extplug_t *ext) | 
init; optional initialization called at prepare or reset
| snd_pcm_chmap_query_t**(* snd_pcm_extplug_callback_t::query_chmaps) (snd_pcm_extplug_t *ext) | 
query the channel maps; optional; since v1.0.2
| int(* snd_pcm_extplug_callback_t::set_chmap) (snd_pcm_extplug_t *ext, const snd_pcm_chmap_t *map) | 
set the channel map; optional; since v1.0.2
| snd_pcm_sframes_t(* snd_pcm_extplug_callback_t::transfer) (snd_pcm_extplug_t *ext, const snd_pcm_channel_area_t *dst_areas, snd_pcm_uframes_t dst_offset, const snd_pcm_channel_area_t *src_areas, snd_pcm_uframes_t src_offset, snd_pcm_uframes_t size) | 
transfer between source and destination; this is a required callback