int func5(int n, ...) {
    void *fptr;
    va_list ap_ch;
    int retval;

    va_start(ap_ch, n);
    fptr = dlsym(_Chmath_handle, "func5_chdl");
    if(fptr == NULL) {
        fprintf(_stderr, "Error: %s(): dlsym(): %s\n", __func__,  dlerror());
        return -1;
    }
    dlrunfun(fptr, &retval, func5, n, ap_ch);
    va_end(ap_ch);
    return retval;
}
