void *silc_scalloc(SilcStack stack, SilcUInt32 items, SilcUInt32 size);

    Allocate memory block of size of `size' from the stack indicated by
    `stack', zero the memory area and return pointer to it.  This
    function allocates aligned memory.  Returns NULL on error.

    Be careful with this function:  do not free the returned pointer
    explicitly and do not save the returned pointer to a permanent
    location.

    If `stack' is NULL this function calls silc_calloc.