Using C# Pointers

Question

How does c# makes use of pointers? If C# is a managed language and the garbage collector does a good job at preventing memory leaks and freeing up memory properly, then what

Answer 1

To use pointers you have to allow unsafe code, and mark the methods using pointers as unsafe. You then have to fix any pointers in memory to make sure the garbage collector doesn't move them:

byte[] buffer = new byte[256];

// fixed ensures the buffer won't be moved and so make your pointers invalid
fixed (byte* ptrBuf = buffer) {
    // ...
}

It is unsafe because, theoretically, you could take a pointer, walk the entire address space, and corrupt or change the internal CLR data structures to, say, change a method implementation. You can't do that in managed code.