malloc returns memory or virtual address space

Question

Does malloc allocate a block of memory on the heap or should it be called Virtual Address Space?

Am I being picky calling it Virtual Address Space or this just the legac

Answer 1

malloc allocates a block on the heap. For each memory page that the allocated block spans, there may or may not be physical memory committed to it at the outset. The entire block is usable though, since the OS will take care of handling page faults and managing physical/virtual memory that's needed to support the allocation.