boundary.
If SIZE is not a multiple of the system page size, it will be rounded up
to the next multiple.
- Return a pointer to the start of the memory block, or NULL if the allocation
- failed. */
+ Return a pointer to the start of the memory block. Upon allocation failure,
+ return NULL and set errno. */
extern void *pagealign_alloc (size_t size);
/* Like pagealign_alloc, except it exits the program if the allocation