Should record audio from speakers. UPD: https://github.com/AshFTW/output-audio-stream

main.cpp

#include <cstdint>
#include <cstring>
#include <unistd.h>
#include <iostream>
#include <portaudio.h>
#include <cmath>

using namespace std;

#define LEN(n) sizeof(n)/sizeof(n[0])
#define SAMPLE int16_t

/* Declaration */
SAMPLE* CaptureBuffer;
bool lastBufferNull = false;

/*
 * Log a PaError to console.
 */
static void log_pa(PaError err) {
    cout << "PortAudio: " << Pa_GetErrorText(err) << endl;
}

/*
 * Record Callback and display sound
 */
static int recordCallback(const void *inputBuffer, void *outputBuffer,
                          unsigned long framesPerBuffer, const PaStreamCallbackTimeInfo *timeInfo,
                          PaStreamCallbackFlags statusFlags, void *userData) {
    /* Declaration */


    /* Since we only use memcpy, these casts are not strictly neccessary. */
//    const SAMPLE *rptr = (SAMPLE*)inputBuffer;
//    SAMPLE *wptr = (SAMPLE*)CaptureBuffer+16;
//
//    if (inputBuffer) {
//        for(int i = 0; i < framesPerBuffer; ++i) {
//            wptr += 2;
//            rptr += 2;
////            cout << *rptr++ << ":";
//        }
//        cout << endl;
//        lastBufferNull = false;
//    } else {
//        if (!lastBufferNull) {
//            cerr<<"Record callback received null buffer"<<endl;
//            lastBufferNull = true;
//        }
//        for (int i = 0; i < framesPerBuffer; ++i) {
//            wptr += 2;
//        }
//    }

//    for (int i = 0; i < framesPerBuffer; i++) {
//        *wptr++ = FUZZ(*rptr++);  /* left - distorted */
//        *wptr++ = *rptr++;          /* right - clean */
//    }

    int16_t *in = (int16_t *) inputBuffer;
    for(int i = 0; i < LEN(in); i++) {
        cout << in[i] << ":";
    }
    cout << endl;
    return paContinue;
}


int main(int argc, char **argv) {
//    PaError err = 0;
//    const PaDeviceInfo *devInfo;
//    const PaStreamInfo *streamInfo;
//    int32_t defaultSampleRate = 44100;
//    char* _CaptureBuffer;
//    char* _CaptureBufferComp;
//    int32_t _CaptureBufferSizeComp = 0x790;
//    int32_t _CurrentCaptureIndexComp = 0x10;
//
//    PaStreamParameters inputParameters;
//    PaStream *stream;
//
//    err = Pa_Initialize();
//    if (err) {
//        cerr << "An error occurred while opening the portaudio stream." << endl;
//        goto error;
//    }
//
//    inputParameters.device = Pa_GetDefaultInputDevice();
//    if (inputParameters.device == -1){
//        cerr<<"Error: No default input device."<<endl;
//        err = -10000;
//        goto error;
//    }
//
//    devInfo = Pa_GetDeviceInfo(inputParameters.device);
//    if (!devInfo) {
//        cerr<<"Error: Invalid default input device."<<endl;
//        err = -10000;
//        goto error;
//    }
//    inputParameters.channelCount = 2;
//    inputParameters.sampleFormat = paInt16;
//    inputParameters.suggestedLatency = devInfo->defaultLowInputLatency;
//    inputParameters.hostApiSpecificStreamInfo = NULL;
//    defaultSampleRate = floor(devInfo->defaultSampleRate + 0.5);
//    clog<<"Portaudio reported default input device sample rate is "<<defaultSampleRate<<" (may not be accurate)"<<endl;
//
////    clog<<"stream size  "<<sizeof(PaStream**)
////        <<", parameters  "<<sizeof(const PaStreamParameters*)
////        <<", double  "<<sizeof(double)
////        <<", unsigned long  "<<sizeof(unsigned long)
////        <<", flags  "<<sizeof(PaStreamFlags)
////        <<", callback  "<<sizeof(PaStreamCallback*)
////        <<", void_p  "<<sizeof(void*)<<endl;
//
////            COERCE_UNSIGNED_INT64((long double)defaultSampleRate),
////            COERCE_UNSIGNED_INT64((long double)defaultSampleRate) >> 32,
////            338,
////            1,
////            Audio::recordCallback,
////            0);
//    //(1234.1234.1234.1234.1234.1234.1234.1234.1234.1234.1234.1234.0000.0000.0000.0152.0000.0000.0000.0001.1234.1234.1234.1234);
//    //(link to stream     .link to input      .link to output     .double             . unsigned long     .PaStreamFlags      .Callback pointer
//    err = Pa_OpenStream(&stream, &inputParameters, NULL, defaultSampleRate, 1, paClipOff, recordCallback, NULL);
//    if (err)
//        goto error;
//
//    err = Pa_StartStream(stream);
//    if (err)
//        goto error;
//
//    streamInfo = Pa_GetStreamInfo(stream);
//    cout<<"Audio stream info: sample rate = "<<streamInfo->sampleRate
//        <<", input latency = "<<streamInfo->inputLatency<<" sec"<<endl;
    /* Initialize. */
    log_pa(Pa_Initialize());
    PaStreamParameters input_parameters;
    /* Set record device (monitor of Default). */
    input_parameters.device = Pa_GetDefaultInputDevice();
    input_parameters.channelCount = 2;
    input_parameters.sampleFormat = paInt16;
    const PaDeviceInfo *input_info = Pa_GetDeviceInfo(input_parameters.device);
    input_parameters.suggestedLatency = input_info->defaultLowInputLatency;
    input_parameters.hostApiSpecificStreamInfo = NULL;

    /* Create and start stream, let it run for 5 seconds, then close it again. */
    PaStream *stream;
    log_pa(Pa_OpenStream(&stream, &input_parameters, NULL, input_info->defaultSampleRate, paFramesPerBufferUnspecified,
                         paClipOff, recordCallback, NULL));
    log_pa(Pa_StartStream(stream));
    Pa_Sleep(5000);
    log_pa(Pa_StopStream(stream));
    log_pa(Pa_CloseStream(stream));
    log_pa(Pa_Terminate());
    cerr<<"ASDLASHDAJSDHAJSDJHALKJSDHJAJKLSJD"<<endl;
    return 0;
//
//    Pa_Sleep(5000000);
//
//    err = Pa_CloseStream(stream);
//    Pa_Terminate();
//    if (err) {
//        cerr<<"An error occured while closing the portaudio stream"<<endl;
//        goto error;
//    }
//
//error:
//    cerr<<"Error message("<<err<<"): "<<Pa_GetErrorText(err)<<endl;
//    return err;
}