Is OS detection possible with GLib?

问题:

Is it possible to determine on which platform (GNU/Linux, Win32, OS X) my Vala app is running?

回答1:

As Vala is a compiled language (as opposed to intermediate or interpreted) you can determine the platform using your favorite build tool and use conditional compilation.

Something like:

#if WINDOWS
    message ("Running on Windows");
#elif OSX
    message ("Running on OS X");
#elif LINUX
    message ("Running on GNU/Linux");
#elif POSIX
    message ("Running on other POSIX system");
#else
    message ("Running on unknown OS");
#endif

The build tool would have to pass -D LINUX, etc to the compiler.

I would be careful and only do something like this as a last resort, because it can backfire. Usually it's better to use cross platform libraries that already handle the differences for you.

BTW: See also how this is done in C++.