This is basically what it is:
http://en.wikipedia.org/wiki/Pragma_once[
^].
It does not say it's only Microsoft, it's "non-standard but widely supported". The argument that C++ is ISO standard makes me Laugh Out Loud.
In my opinion, the problem is not "
#once
", the problem is "
#ever
" :-). We still have "
#include
", in XXI century — my congratulations, Ladies and Gentlemen.
Thanks goodness, I had enough alternatives even in the world of native-platform programming and in lowest level.
—SA