What C preprocessor conditional should I use for OS X specific code?

c, c-preprocessor, conditional-compilation, macos

Solution

This list of operating system macros says the presence of both `__APPLE__` and `__MACH__` indicate OSX.

Also confirmed at line 18 of part of the source for `fdisk`.

Problem

What C preprocessor conditional should I use for OS X specific code? I need to include a specific library if I am compiling for OS X or a different header if I am compiling for Linux. I know there is `__APPLE__` but I don't know if that is a current conditional for OS X 10.x.

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