test/pcm_min.c

   1 /*
   2  *  This extra small demo sends a random samples to your speakers.
   3  */
   4
   5 #include "../include/asoundlib.h"
   6
   7 static char *device = "default";                        /* playback device */
   8 unsigned char buffer[16*1024];                          /* some random data */
   9
  10 int main(void)
  11 {
  12         int err;
  13         unsigned int i;
  14         snd_pcm_t *handle;
  15         snd_pcm_sframes_t frames;
  16
  17         for (i = 0; i < sizeof(buffer); i++)
  18                 buffer[i] = random() & 0xff;
  19
  20         if ((err = snd_pcm_open(&handle, device, SND_PCM_STREAM_PLAYBACK, 0)) < 0) {
  21                 printf("Playback open error: %s\n", snd_strerror(err));
  22                 exit(EXIT_FAILURE);
  23         }
  24         if ((err = snd_pcm_set_params(handle,
  25                                       SND_PCM_FORMAT_U8,
  26                                       SND_PCM_ACCESS_RW_INTERLEAVED,
  27                                       1,
  28                                       48000,
  29                                       1,
  30                                       500000)) < 0) {   /* 0.5sec */
  31                 printf("Playback open error: %s\n", snd_strerror(err));
  32                 exit(EXIT_FAILURE);
  33         }
  34
  35         for (i = 0; i < 16; i++) {
  36                 frames = snd_pcm_writei(handle, buffer, sizeof(buffer));
  37                 if (frames < 0)
  38                         frames = snd_pcm_recover(handle, frames, 0);
  39                 if (frames < 0) {
  40                         printf("snd_pcm_writei failed: %s\n", snd_strerror(frames));
  41                         break;
  42                 }
  43                 if (frames > 0 && frames < (long)sizeof(buffer))
  44                         printf("Short write (expected %li, wrote %li)\n", (long)sizeof(buffer), frames);
  45         }
  46
  47         /* pass the remaining samples, otherwise they're dropped in close */
  48         err = snd_pcm_drain(handle);
  49         if (err < 0)
  50                 printf("snd_pcm_drain failed: %s\n", snd_strerror(err));
  51         snd_pcm_close(handle);
  52         return 0;
  53 }