#define _DEFAULT_SOURCE
#include <unistd.h>
#include <stdio.h>
#include <errno.h>
#include <stdlib.h>

int main(void)
{
    char c;
    int ret;

    ret = getentropy(&c, sizeof(c));
    if (ret == -1) {
        perror("getentropy");
        return 1;
    }
    fprintf(stderr, "success\n");
    return 0;
}