Basic pulseaudio initialisation

gistfile1.c

/* For instance... */
#define BUFSIZE 1024

pa_simple *init_pulse(int *perror)
{
    /* The sample type to use.  
       This gives us 2 channels of 8 bits per channel. */
    static const pa_sample_spec ss = {
        .format = PA_SAMPLE_U8,
        .rate = 44100,
        .channels = 2
    };

    /*
      // Debug info on the sample type we've got if you're interested
       printf("Bytes per second:\t%d\n", (int)pa_bytes_per_second(&ss));
       printf("Frame size:\t%d\n", (int)pa_frame_size(&ss));
       printf("Sample size\t%d\n", (int)pa_sample_size(&ss));
    */

    /* The only important bit here is BUFSIZE, where we tell Pulse
       how many samples we want at a time */
    static const pa_buffer_attr ba = {
      .maxlength = -1,
      .tlength = -1,
      .prebuf = -1,
      .minreq = -1,
      .fragsize = BUFSIZE
    };

    pa_channel_map cm;
    pa_channel_map_init_stereo(&cm);

    return pa_simple_new(NULL, 
                         __FILE__, 
                         PA_STREAM_RECORD, 
                         NULL, 
                         "record", 
                         &ss, 
                         &cm, 
                         &ba, 
                         perror);
}

/* Now, during the main() somewhere:  */

    pa_simple *stream = init_pulse(&pulse_error);

    /* Some time later... */

    uint8_t buf[BUFSIZE*2];

    for ( ; ; ) {
      /* Record some data ... */
      if (pa_simple_read(stream, buf, sizeof(buf), &pulse_error) < 0) {
        fprintf(stderr, __FILE__": pa_simple_read() failed: %s\n", 
                pa_strerror(pulse_error));
        goto finish;
      }

      /* Now buf will contain 1024 left/right sample byte pairs. */
      do_something_with( buf );
    }