Naming Include Guards

Question

How are C++ include guards typically named? I tend to see this a lot:

#ifndef FOO_H
#define FOO_H

// ...

#endif

However, I don\'t think

Answer 1

Usually people do that by file name so that each file's code only gets compiled and added once. You could make FOO_H whatever you want, but almost everything I've ever coded or seen has used the file name. Just make sure it's unique because you don't want your FOO_H conflicting with someone else's FOO_H.