When including header files, is the path case sensitive?

Question

Given this directory tree:

src/MyLibrary/MyHeader.h
src/file.cpp

file.cpp:

#include "mylibrary/myheader.h"
...

Compiling file.cpp works with VS, fails in gcc.

• What does the standard say?
• If the path is case sensitive, why is this wise?
• What's the best practice, keep all file/folder names lowercase and thus do the same when including?

Thanks.

Answer 1

The case sensitivity depends on the Operating System. Windows is not case sensitive. Linux is.

EDIT:

Actually, as observed by Martin York's comment, the case sensitivity depends on the file system. By default Windows uses a case insensitive file system, while Linux uses a case sensitive one. For whoever is interested to know which file systems are case sensitive and which aren't, there is a comprehensive list on Wikipedia: Comparison of file name limitations.