Windows utilizza la sua unica e unica architettura audio, quindi puoi accedere a sound()
routine.
Diverse macchine Linux, a seconda dei pacchetti installati, possono richiedere approcci diversi. Forse l'utility beep
(fuori da questa domanda su StackExchange) può guidarti nella giusta direzione
Mi piace il suggerimento sopra riguardante libao:l'ho appena provato e funziona bene. Ecco un livello di complessità simile utilizzando OpenAL per sintetizzare un buffer audio non elaborato in formato PCM e quindi eseguire il rendering come audio
// sudo apt-get install libopenal-dev
// gcc -o openal_play_monday openal_play_monday.c -lopenal -lm
#include <stdio.h>
#include <stdlib.h> // gives malloc
#include <math.h>
#ifdef __APPLE__
#include <OpenAL/al.h>
#include <OpenAL/alc.h>
#elif __linux
#include <AL/al.h>
#include <AL/alc.h>
#include <unistd.h>
#endif
ALCdevice * openal_output_device;
ALCcontext * openal_output_context;
ALuint internal_buffer;
ALuint streaming_source[1];
int al_check_error(const char * given_label) {
ALenum al_error;
al_error = alGetError();
if(AL_NO_ERROR != al_error) {
printf("ERROR - %s (%s)\n", alGetString(al_error), given_label);
return al_error;
}
return 0;
}
void MM_init_al() {
const char * defname = alcGetString(NULL, ALC_DEFAULT_DEVICE_SPECIFIER);
openal_output_device = alcOpenDevice(defname);
openal_output_context = alcCreateContext(openal_output_device, NULL);
alcMakeContextCurrent(openal_output_context);
// setup buffer and source
alGenBuffers(1, & internal_buffer);
al_check_error("failed call to alGenBuffers");
}
void MM_exit_al() {
ALenum errorCode = 0;
// Stop the sources
alSourceStopv(1, & streaming_source[0]); // streaming_source
int ii;
for (ii = 0; ii < 1; ++ii) {
alSourcei(streaming_source[ii], AL_BUFFER, 0);
}
// Clean-up
alDeleteSources(1, &streaming_source[0]);
alDeleteBuffers(16, &streaming_source[0]);
errorCode = alGetError();
alcMakeContextCurrent(NULL);
errorCode = alGetError();
alcDestroyContext(openal_output_context);
alcCloseDevice(openal_output_device);
}
void MM_render_one_buffer() {
/* Fill buffer with Sine-Wave */
// float freq = 440.f;
float freq = 100.f;
float incr_freq = 0.1f;
int seconds = 4;
// unsigned sample_rate = 22050;
unsigned sample_rate = 44100;
double my_pi = 3.14159;
size_t buf_size = seconds * sample_rate;
// allocate PCM audio buffer
short * samples = malloc(sizeof(short) * buf_size);
printf("\nhere is freq %f\n", freq);
int i=0;
for(; i<buf_size; ++i) {
samples[i] = 32760 * sin( (2.f * my_pi * freq)/sample_rate * i );
freq += incr_freq; // change freq just to make things interesting
if (100.0 > freq || freq > 5000.0) {
incr_freq *= -1.0f; // toggle direction of freq increment
}
}
/* upload buffer to OpenAL */
alBufferData( internal_buffer, AL_FORMAT_MONO16, samples, buf_size, sample_rate);
al_check_error("populating alBufferData");
free(samples);
/* Set-up sound source and play buffer */
// ALuint src = 0;
// alGenSources(1, &src);
// alSourcei(src, AL_BUFFER, internal_buffer);
alGenSources(1, & streaming_source[0]);
alSourcei(streaming_source[0], AL_BUFFER, internal_buffer);
// alSourcePlay(src);
alSourcePlay(streaming_source[0]);
// ---------------------
ALenum current_playing_state;
alGetSourcei(streaming_source[0], AL_SOURCE_STATE, & current_playing_state);
al_check_error("alGetSourcei AL_SOURCE_STATE");
while (AL_PLAYING == current_playing_state) {
printf("still playing ... so sleep\n");
sleep(1); // should use a thread sleep NOT sleep() for a more responsive finish
alGetSourcei(streaming_source[0], AL_SOURCE_STATE, & current_playing_state);
al_check_error("alGetSourcei AL_SOURCE_STATE");
}
printf("end of playing\n");
/* Dealloc OpenAL */
MM_exit_al();
} // MM_render_one_buffer
int main() {
MM_init_al();
MM_render_one_buffer();
}
Se vuoi portare OpenAL oltre... dai un'occhiata a questo
https://github.com/scottstensland/render-audio-openal
Out of the box OpenAL riproduce bene un buffer di audio PCM ... tuttavia lascia come esercizio la possibilità di riprodurre un flusso. In quel repository github ho scritto un server audio usando OpenAL che implementa la riproduzione di audio in streaming ... buon divertimento