tiny-tinyalsa-test

/*
 *  This tiny demo sends random samples to your speakers.
 */
#include <tinyalsa/asoundlib.h>
#include <stdlib.h>
#include <stdio.h>
#include <errno.h>
#define RATE 44100
struct pcm *dev;
struct pcm_config cfg;
unsigned char buffer[1024]; /* some random data */

int main(void)
{
        int err;
        unsigned int i;
        for (i = 0; i < sizeof(buffer); i++) buffer[i] = rand() & 0xff;

        // Set config values, drawing info from:
        // pactl list short sinks
        // 0    alsa_output.pci-0000_00_03.0.hdmi-stereo    module-alsa-card.c  s16le 2ch 44100Hz   SUSPENDED
        // 1    alsa_output.pci-0000_00_1b.0.analog-stereo  module-alsa-card.c  s16le 2ch 44100Hz   SUSPENDED
        cfg.channels = 2;
        cfg.rate = RATE;
        cfg.period_size = 4;
        cfg.period_count = RATE; // 1 sec
        cfg.format = PCM_FORMAT_S16_LE;
        cfg.start_threshold = 0;
        cfg.stop_threshold = 0;
        cfg.silence_threshold = 0;

        printf("errno %d\n", errno); // 0
        dev = pcm_open(1, 0, PCM_OUT, &cfg);
        printf("errno %d\n", errno); // 22
        err = pcm_start(dev);
        printf("errno %d\n", errno); // 9
        err = pcm_write(dev, &buffer, 1024);
        printf("errno %d\n", errno); // 9
        err = pcm_close(dev);
        printf("errno %d\n", errno); // 9
        return 0;
}