Audio Library
This chapter describes all of the supported QSA API functions, in alphabetical order; undocumented calls aren't supported.
The QNX Sound Architecture (QSA) has similarities to the Advanced Linux Sound Architecture (ALSA), but isn't compatible. Though the function names may be the same, there's no guarantee that QSA and ALSA calls behave the same (some definitely don't).
For information about the sections in each description, see the What's in a Function Description? chapter of the QNX Neutrino C Library Reference.
Related links
- snd_card_get_longname()
Find the long name for a given card number
- snd_card_get_name()
Find the name for a given card number
- snd_card_name()
Find the card number for a given name
- snd_cards()
Count the sound cards
- snd_cards_list()
Count the sound cards and list their card numbers in an array
- snd_ctl_callbacks_t
Control callback functions
- snd_ctl_close()
Close a control handle
- snd_ctl_file_descriptor()
Get the control file descriptor
- snd_ctl_hw_info()
Get information about a sound card's hardware
- snd_ctl_hw_info_t
Information about a sound card's hardware
- snd_ctl_mixer_switch_list()
Get the number and names of control switches for the mixer
- snd_ctl_mixer_switch_read()
Get a mixer switch setting
- snd_ctl_mixer_switch_write()
Adjust a mixer switch setting
- snd_ctl_open()
Create a connection and handle to the specified control device
- snd_ctl_pcm_channel_info()
Get information about a PCM channel's capabilities from a control handle
- snd_ctl_pcm_info()
Get general information about a PCM device from a control handle
- snd_ctl_read()
Read pending control events
- snd_mixer_callbacks_t
List of mixer callback functions
- snd_mixer_close()
Close a mixer handle
- snd_mixer_eid_t
Mixer element ID structure
- snd_mixer_element_read()
Get a mixer element's configurable parameters
- snd_mixer_element_t
Mixer element control structure
- snd_mixer_element_write()
Set a mixer element's configurable parameters
- snd_mixer_elements()
Get the number of elements in the mixer and their element IDs
- snd_mixer_elements_t
Information about all elements in a mixer
- snd_mixer_file_descriptor()
Return the file descriptor of the connection to the sound mixer interface
- snd_mixer_filter_t
Information about a mixer's filters
- snd_mixer_get_bit()
Return the boolean value of a single bit in the specified bitmap
- snd_mixer_get_filter()
Get the current mask of mixer events that the driver is tracking
- snd_mixer_gid_t
Mixer group ID structure
- snd_mixer_group_read()
Get a mixer group's configurable parameters
- snd_mixer_group_t
Mixer group control structure
- snd_mixer_group_write()
Set a mixer group's configurable parameters
- snd_mixer_groups()
Get the number of groups in the mixer and their group IDs
- snd_mixer_groups_t
Information about all of the mixer groups
- snd_mixer_info()
Get general information about a mixer device
- snd_mixer_info_t
Information about a mixer
- snd_mixer_open()
Create a connection and handle to a specified mixer device
- snd_mixer_open_name()
Create a connection and handle to a mixer device specified by name
- snd_mixer_read()
Read pending mixer events
- snd_mixer_routes()
Get the number of routes in the mixer and their IDs
- snd_mixer_routes_t
Information about mixer routes
- snd_mixer_set_bit()
Set the boolean value of a single bit in the specified bitmap
- snd_mixer_set_filter()
Set the mask of mixer events that the driver will track
- snd_mixer_sort_eid_table()
Sort a list of element ID structures
- snd_mixer_sort_gid_table()
Sort a list of group ID structures
- snd_mixer_weight_entry_t
Weight table for sorting mixer element and group IDs
- snd_pcm_build_linear_format()
Encode a linear format value
- snd_pcm_capture_flush()
Discard all pending data in a PCM capture channel's queue and stop the channel
- snd_pcm_capture_prepare()
Signal the driver to ready the capture channel
- snd_pcm_channel_flush()
Flush all pending data in a PCM channel's queue and stop the channel
- snd_pcm_channel_info()
Get information about a PCM channel's current capabilities
- snd_pcm_channel_info_t
Information structure for a PCM channel
- snd_pcm_channel_params()
Set a PCM channel's configurable parameters
- snd_pcm_channel_params_t
PCM channel parameters
- snd_pcm_channel_prepare()
Signal the driver to ready the specified channel
- snd_pcm_channel_setup()
Get the current configuration for the specified PCM channel
- snd_pcm_channel_setup_t
Current configuration of a PCM channel
- snd_pcm_channel_status()
Get the runtime status of a PCM channel
- snd_pcm_channel_status_t
PCM channel status structure
- snd_pcm_close()
Close a PCM handle and free its resources
- snd_pcm_file_descriptor()
Return the file descriptor of the connection to the PCM interface
- snd_pcm_find()
Find all PCM devices in the system that meet the given criteria
- snd_pcm_format_big_endian()
Check for a big-endian format
- snd_pcm_format_linear()
Check for a linear format
- snd_pcm_format_little_endian()
Check for a little-endian format
- snd_pcm_format_signed()
Check for a signed format
- snd_pcm_format_size()
Convert the size in the given samples to bytes
- snd_pcm_format_t
PCM data format structure
- snd_pcm_format_unsigned()
Check for an unsigned format
- snd_pcm_format_width()
Return the sample width in bits for a format
- snd_pcm_get_format_name()
Convert a format value into a human-readable text string
- snd_pcm_info()
Get general information about a PCM device
- snd_pcm_info_t
Capability information about a PCM device
- snd_pcm_nonblock_mode()
Set or reset the blocking behavior of reads and writes to PCM channels
- snd_pcm_open()
Create a handle and open a connection to a specified audio interface
- snd_pcm_open_name()
Create a handle and open a connection to an audio interface specified by name
- snd_pcm_open_preferred()
Create a handle and open a connection to the preferred audio interface
- snd_pcm_playback_drain()
Stop the PCM playback channel and discard the contents of its queue
- snd_pcm_playback_flush()
Play out all pending data in a PCM playback channel's queue and stop the channel
- snd_pcm_playback_prepare()
Signal the driver to ready the playback channel
- snd_pcm_plugin_flush()
Finish processing all pending data in a PCM channel's queue and stop the channel
- snd_pcm_plugin_get_voice_conversion()
Get the current voice conversion structure for a channel
- snd_pcm_plugin_info()
Get information about a PCM channel's capabilities (plugin-aware)
- snd_pcm_plugin_params()
Set the configurable parameters for a PCM channel (plugin-aware)
- snd_pcm_plugin_playback_drain()
Stop the PCM playback channel and discard the contents of its queue (plugin-aware)
- snd_pcm_plugin_prepare()
Signal the driver to ready the specified channel (plugin-aware)
- snd_pcm_plugin_read()
Transfer PCM data from the capture channel (plugin-aware)
- snd_pcm_plugin_set_disable()
Disable PCM plugins
- snd_pcm_plugin_set_src_mode()
Set the system's source mode (plugin-aware)
- snd_pcm_plugin_set_voice_conversion()
Set the current voice conversion structure for a channel
- snd_pcm_plugin_setup()
Get the current configuration for the specified PCM channel (plugin aware)
- snd_pcm_plugin_src_max_frag()
Get the maximum possible fragment size (plugin-aware)
- snd_pcm_plugin_status()
Get the runtime status of a PCM channel (plugin aware)
- snd_pcm_plugin_update_src()
Get the size of the next fragment to write (plugin-aware)
- snd_pcm_plugin_write()
Transfer PCM data to playback channel (plugin-aware)
- snd_pcm_read()
Transfer PCM data from the capture channel
- snd_pcm_voice_conversion_t
Data structure that controls voice conversion
- snd_pcm_write()
Transfer PCM data to playback channel
- snd_strerror()
Convert an error code to a string
- snd_switch_t
Information about a mixer's switch