#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/sysctl.h>
int main(void) {
    char out[256];
    size_t len = sizeof(out) - 1;
    int i, j;
    memset(out, 0, sizeof(out));
    /* 1: kstack canary spray in this thread (rig sysctl) */
    if (sysctlbyname("dev.dfsm.0.spray", NULL, NULL, NULL, 0) < 0)
        perror("spray");
    /* 2: PRODUCTION fanid handler in the same thread */
    if (sysctlbyname("dev.dfsm.0.fanid", out, &len, NULL, 0) < 0) {
        perror("fanid");
        return 1;
    }
    printf("fanid returned %zu bytes:\n", len);
    printf("hex: ");
    for (i = 0; i < (int)len && i < 128; i++)
        printf("%02x", (unsigned char)out[i]);
    printf("\nascii: '");
    for (j = 0; j < (int)len && j < 128; j++)
        putchar(out[j] >= 32 && out[j] < 127 ? out[j] : '.');
    printf("'\n");
    return 0;
}