are longer #include paths ever actually needed?
<p>For example, if I had a file called foo.h, can I always just include it by doing:</p>

<pre><code>#include "foo.h"
</code></pre>

<p>or do I sometimes have to do something like:</p>

<pre><code>#include "bar/foobar/foo.h"
</code></pre>

<p>EDIT - are they simply used to make the compile time shorter by limiting the search for the file?</p>
