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#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/ioctl.h>
#include <linux/soundcard.h>
int main (void)
{
short buf[256*2*100];
int hifi, precision=8, stereo=1, rate=8000, odelay, old = 0x7ffffff, x;
hifi = open ("/dev/dsp", O_WRONLY);
if (hifi < 0 ||
ioctl(hifi, SNDCTL_DSP_SAMPLESIZE, &precision) == -1 ||
ioctl(hifi, SNDCTL_DSP_STEREO, &stereo) == -1 ||
ioctl(hifi, SNDCTL_DSP_SPEED, &rate) == -1) {
fprintf (stderr, "Unable to open sound device\n");
return 3;
}
memset(buf, 0, sizeof(buf));
write(hifi, buf, sizeof(buf));
for (x=0;;x++) {
//usleep (50000); // Take this out, to experiment
if (ioctl (hifi, SNDCTL_DSP_GETODELAY, &odelay) < 0) {
perror("ioctl");
return 4;
}
if (old != odelay) {
printf ("%c %10d %10d\n", old < odelay ? '*' : ' ', odelay, odelay % 256);
old = odelay;
}
if (odelay == 0)
break;
}
return 0;
}
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