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#ifndef PA_LINUX_ALSA_H
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#define PA_LINUX_ALSA_H
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* $Id: pa_linux_alsa.h 1597 2011-02-11 00:15:51Z dmitrykos $
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* PortAudio Portable Real-Time Audio Library
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* ALSA-specific extensions
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* Copyright (c) 1999-2000 Ross Bencina and Phil Burk
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* Permission is hereby granted, free of charge, to any person obtaining
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* a copy of this software and associated documentation files
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* (the "Software"), to deal in the Software without restriction,
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* including without limitation the rights to use, copy, modify, merge,
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* publish, distribute, sublicense, and/or sell copies of the Software,
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* and to permit persons to whom the Software is furnished to do so,
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* subject to the following conditions:
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* The above copyright notice and this permission notice shall be
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* included in all copies or substantial portions of the Software.
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* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
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* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
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* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
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* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR
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* ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF
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* CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
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* WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
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* The text above constitutes the entire PortAudio license; however,
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* the PortAudio community also makes the following non-binding requests:
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* Any person wishing to distribute modifications to the Software is
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* requested to send the modifications to the original developer so that
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* they can be incorporated into the canonical version. It is also
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* requested that these non-binding requests be included along with the
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* @ingroup public_header
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* @brief ALSA-specific PortAudio API extension header file.
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#include "portaudio.h"
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typedef struct PaAlsaStreamInfo
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PaHostApiTypeId hostApiType;
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unsigned long version;
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const char *deviceString;
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/** Initialize host API specific structure, call this before setting relevant attributes. */
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void PaAlsa_InitializeStreamInfo( PaAlsaStreamInfo *info );
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/** Instruct whether to enable real-time priority when starting the audio thread.
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* If this is turned on by the stream is started, the audio callback thread will be created
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* with the FIFO scheduling policy, which is suitable for realtime operation.
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void PaAlsa_EnableRealtimeScheduling( PaStream *s, int enable );
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void PaAlsa_EnableWatchdog( PaStream *s, int enable );
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/** Get the ALSA-lib card index of this stream's input device. */
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PaError PaAlsa_GetStreamInputCard( PaStream *s, int *card );
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/** Get the ALSA-lib card index of this stream's output device. */
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PaError PaAlsa_GetStreamOutputCard( PaStream *s, int *card );
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/** Set the number of periods (buffer fragments) to configure devices with.
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* By default the number of periods is 4, this is the lowest number of periods that works well on
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* the author's soundcard.
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* @param numPeriods The number of periods.
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PaError PaAlsa_SetNumPeriods( int numPeriods );
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/** Set the maximum number of times to retry opening busy device (sleeping for a
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* short interval inbetween).
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PaError PaAlsa_SetRetriesBusy( int retries );
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/** Set the path and name of ALSA library file if PortAudio is configured to load it dynamically (see
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* PA_ALSA_DYNAMIC). This setting will overwrite the default name set by PA_ALSA_PATHNAME define.
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* @param pathName Full path with filename. Only filename can be used, but dlopen() will lookup default
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* searchable directories (/usr/lib;/usr/local/lib) then.
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void PaAlsa_SetLibraryPathName( const char *pathName );