Reserve memory on OS X

Question

What's the equivalent to Windows's VirtualAlloc in OS X? That is, how can i reserve a contiguous address space without actually commiting it and then commit chunks of it later?

Thanks,

Alex

Answer 1

The mmap() function, called with MAP_ANON | MAP_PRIVATE, is very roughly equivalent to VirtualAlloc() with the MEM_RESERVE flag. Memory is then committed by touching each page in the mapping.