title: <png.h> not found in mac os X mavericks
body: <p>I tried (apparently successfully) to install <code>libpng</code> on mac os x mavericks.</p>
  
  <p>I downloaded the latest 1-6-8 version <code>.tar.xz</code> and followed the instructions.</p>
  
  <p><code>./configure</code> runs fine</p>
  
  <p><code>make check</code> passes everything but png-error that gets skipped</p>
  
  <p><code>sudo make install</code> apparently works fine since my library libpng. appears.</p>
  
  <p>Now, when i try to compile the C file that i need to compile, using the string </p>
  
  <p><code>clang -w -lz -lpng16 libpng_test.c</code></p>
  
  <p>i get the error</p>
  
  <p><code>fatal error: 'png.h' file not found</code></p>
  
  <p><code>#include &lt;png.h&gt;</code></p>
  
  <p>and obviously it does not compile.</p>
  
  <p>I tried installing both with homebrew and macports and it always seems to run fine, but i always get the same error</p>