/*
 * magic_check
 *
 * Make sure the stored data we're trying to retrieve has been produced
 * on an ILP compatible system with the same byteorder. It croaks out in
 * case an error is detected. [ILP = integer-long-pointer sizes]
 * Returns null if error is detected, &PL_sv_undef otherwise.
 *
 * Note that there's no byte ordering info emitted when network order was
 * used at store time.
 */
static SV *magic_check(pTHX_ stcxt_t *cxt)
{

    ...


    current = buf + c;
    
    /* sizeof(int) */
    if ((int) *current++ != sizeof(int))
        CROAK(("Integer size is not compatible"));

    /* sizeof(long) */
    if ((int) *current++ != sizeof(long))
        CROAK(("Long integer size is not compatible"));

    /* sizeof(char *) */
    if ((int) *current != sizeof(char *))
        CROAK(("Pointer size is not compatible"));

    if (use_NV_size) {
        /* sizeof(NV) */
        if ((int) *++current != sizeof(NV))
            CROAK(("Double size is not compatible"));
    }

    return &PL_sv_undef;	/* OK */
}