NAME
malloc_good_size, malloc_size – memory allocation information
SYNOPSIS
#include <malloc/malloc.h>
size_t
malloc_good_size(size_t size);
size_t
malloc_size(const void *ptr);
DESCRIPTION
The malloc_size() function returns the size of the memory block that backs the allocation pointed to by ptr. The memory block size is always at least as large as the allocation it backs, and may be larger.
The malloc_good_size() function rounds size up to a value that the allocator implementation can allocate without adding any padding; it then returns that rounded-up value.