An absolute path is a valid path on the filesystem. But the compiler should be searching according to its implementation dependent search paths, when doing <>.

An absolute path is a valid path on the filesystem. But the compiler should be searching according to its implementation dependent search paths, when doing <>. Not prepending the searchpath (and not rejecting) for absolute paths is an implementation choice I personally think is wrong for a C compiler. But it may be able to do so I guess as you can also do "..".