Create a handle and open a connection to an audio interface specified by name
#include <sys/asoundlib.h> int snd_pcm_open_name( snd_pcm_t **handle, char *name, int mode );
- A pointer to a location where snd_pcm_open_name() can store a handle for the audio interface. You'll need this handle when you call the other snd_pcm_* functions.
- The name of the PCM device to open; one of the following:
Use this device: For: pcmPreferred The default to use under most circumstances tones The default to use for system sounds. Sounds played through this device aren't attenuated by the global volume setting. bluetooth Accessing a Bluetooth headset voice Acoustic echo cancellation and noise suppression, as well as lower latency hdmi_mix Playback through a receiver connected over HDMI usb_mix Playback through a receiver connected over USB usb Capture over a microphone connected over USB
- One of:
- SND_PCM_OPEN_PLAYBACK — open the playback channel (direction).
- SND_PCM_OPEN_CAPTURE — open the capture channel (direction).
You can OR the following flag with any of the above:
SND_PCM_OPEN_NONBLOCK — force the mode to be
This affects any reading from or writing to the device that you do later;
you can query the device any time without blocking.
You can change the blocking setup later by calling snd_pcm_nonblock_mode().
Use the -l asound option to qcc to link against this library.
The snd_pcm_open_name() function creates a handle and opens a connection to the named PCM audio interface.
- The state of handle is invalid, the mode is invalid, or an invalid state change occurred. You can call snd_pcm_channel_status() to check if the state change was invalid.
- The named device doesn't exist.
- Not enough memory is available to allocate the control structures.
- The audio driver version is incompatible with the client library that the application is using.
snd_pcm_open_name(&pcm_handle, "voice", SND_PCM_OPEN_CAPTURE);
See also the example of snd_pcm_open() in " Opening your PCM device " in the Playing and Capturing Audio Data chapter.
|Thread||Read the Caveats|
This function is not thread safe if handle (snd_pcm_t) is used across multiple threads.
Successfully opening a PCM channel doesn't guarantee that there are enough audio resources free to handle your application. Audio resources (e.g. subchannels) are allocated when you configure the channel by calling snd_pcm_channel_params() or snd_pcm_plugin_params().
Last modified: 2014-06-24