When to use pointers in C#/.NET?

Question

I know C# gives the programmer the ability to access, use pointers in an unsafe context. But When is this needed?

At what circumstances, using pointers becomes inevi

Answer 1

Say you want to communicate between 2 application using IPC (shared memory) then you can marshal the data to memory and pass this data pointer to the other application via windows messaging or something. At receiving application you can fetch data back.

Useful also in case of transferring data from .NET to legacy VB6 apps wherein you will marshal the data to memory, pass pointer to VB6 app using win msging, use VB6 copymemory() to fetch data from the managed memory space to VB6 apps unmanaged memory space..