[CMake] When are these set: APPLE, etc *AND* documentation ERROR

[Miguel A. Figueroa-Villanueva]

Hello,

I'm reviewing a few CMake variables used to determine the platform we
are in. I'm looking at the "cmake --help-variable" output and at the
wiki (http://www.cmake.org/Wiki/CMake_Useful_Variables).

I found a discrepancy, which should be fixed. In the help output for
APPLE it returns: True if running on Mac OSX. However, the wiki says
that it will return TRUE for other APPLE (non-macosx) systems as well.
Also, are MINGW and MSYS variables "official"?; there documentation is
not available in the help.

More to the point of my question, since I don't have a few of these
platforms available, I would like to ask for help verifying the
following assumptions:

1. UNIX is TRUE in msys systems, right?

2. UNIX is FALSE in mingw systems that do not have the msys shell
installed, right?

3. WIN32 is TRUE in both mingw and msys systems, right?

Thanks,
--Miguel