Other than malloc/free does a program need the OS to provide anything else?

Question

I\'m working on designing the kernel (which I\'m going to actually call the \"core\" just to be different, but its basically the same) for an OS I\'m working on. The specifics o

Answer 1

There are multiple ways to tackle the problem.

Most often C programs have their own malloc/free functionality. That one will work for the small objects. Initially (and as soon as the memory is exhausted) the memory manager will ask the OS for more memory. Traditional methods to do this are mmap and sbrk on the unix variants (GlobalAlloc / LocalAlloc on Win32).

I suggest that you take a look at the Doug Lea memory allocator (google: dlmalloc) from a memory provider (e.g. OS) point of view. That allocator is top notch in a very good one and has hooks for all major operation system. If you want to know what a high performance allocator expects from an OS this is code is your first choice.