C++: Reason why using ".hh" as extension for C++ header files [closed]

Question

I would like to know why we use ".hh" as extension for C++ header files instead of using just ".h".

The header files are preprocessed and the preprocessor doesn't even care about the extension of the header file. So, even if I create a header file with an extension ".qwe" (test.qwe). Then, why to use ".hh" as extension for C++ header files.

Some say, we are using ".cc" as extension for C++ files to differentiate from C files (which has an extension ".c"), likewise we are using using ".hh" as extension for C++ header files to differentiate from C header files (which has an extension ".h"). I don't think this to be a valid reason.

Does anyone know the reason for naming in such a way?

Answer 1

Some say, we are using ".cc" as extension for C++ files to differentiate from C files (which has an extension ".c"), likewise we are using using ".hh" as extension for C++ header files to differentiate from C header files (which has an extension ".h").

That is exactly the reason. It is just to differentiate CPP headers from C headers.

Some programmers and libraries, such as Boost, use .hpp for CPP headers. My personal choice is this:

• example.c
• example.cpp
• example.h
• example.h++

Even if they all belong to a huge project, you can still figure out which one is which. No description is needed.