int main(int argc, char *argv[])
{
    int c;
    extern char  *optarg;
    extern int    optind, optopt, opterr;

    kern_return_t result;
    int          op = OP_NONE;
    UInt32Char_t  key = "\0";
    SMCVal_t      val;

    while ((c = getopt(argc, argv, "fhk:lrw:v")) != -1)
    {
        switch(c)
        {
        case 'f':
            op = OP_READ_FAN;
            break;
        case 'k':
            sprintf(key, optarg); // Overflow !!!
            break;