Here's a quick note on how to list the 'include path' used by gcc, to find header files (e.g. 'stdout.h').

	$ gcc -v -x c /dev/null
	...
	...
	#include "..." search starts here:
	#include <...> search starts here:
	 /usr/local/include
	 /usr/lib/gcc/x86_64-linux-gnu/4.4.5/include
	 /usr/lib/gcc/x86_64-linux-gnu/4.4.5/include-fixed
	 /usr/include
	End of search list.
	...
	...