SIZE_T (FIXME: obsolete?)
If possible, avoid size_t and use unsigned long instead. If not,
#include <sys/types.h> in all files manipulating size_t
- do cast it to unsigned long before printing (and use %lu)
+ do cast it to unsigned long before printing (and use %lu),
+ or use %zu.
PRINTF pointer difference (FIXME: advertise %td instead?)
printf ("diff = %ld\n", (long) (pointer2 - pointer1));
