#include <assert.h>
#include <unistd.h>
int main() {
char buf[256] = {0};
int ret = getentropy(buf, 256);
assert(ret == 0);
int sum = 0;
for (int i = 0; i < 256; i++) {
sum += buf[i];
}
assert(sum != 0);
return 0;