title: What does this line mean? LOCAL_EXPORT_C_INCLUDES
body: <p>Very simple question, hoping for a very simple answer.  I've been looking at a lot of people's android.mk files and have noticed this line.  I had no documentation on it within my NDK's docs (at least <code>find . -name "*.txt" | xargs grep "LOCAL_EXPORT_C_INCLUDES"</code> came up with nothing).  This was the only documentation I've read on it...goes way over my head...</p>
  
  <p>Part 2: Am I correct in my assumption that I will need this line to use a pre-built shared library with another module?  Thanks guys (and gals)</p>
  
  <blockquote>
    <h2>III. Exporting headers for prebuilt libraries:</h2>
    
    <p>The example above was called 'naive' because, in practice, the code in
    foo-user.c is going to depend on specific declarations that are normally
    found in a header file distributed with the prebuilt library (e.g. "foo.h").</p>
    
    <p>In other words, foo-user.c is going to have a line like:</p>
    
    <h1>include &lt; foo.h ></h1>
    
    <p>And you need to provide the header and its include path to the compiler
    when building the foo-user module.
    A simple way to deal with that is to use exports in the prebuilt module
    definition. For example, assuming that a file "foo.h" is located under
    the 'include' directory relative to the prebuilt module, we can write:</p>
    
    <p>`include $(CLEAR_VARS)</p>
    
    <p>LOCAL_MODULE := foo-prebuilt</p>
    
    <p>LOCAL_SRC_FILES := libfoo.so</p>
    
    <p>LOCAL_EXPORT_C_INCLUDES := $(LOCAL_PATH)/include</p>
    
    <p>include $(PREBUILT_SHARED_LIBRARY)`</p>
    
    <p>The LOCAL_EXPORT_C_INCLUDES definition here ensures that any module that
    depends on the prebuilt one will have its LOCAL_C_INCLUDES automatically
    prepended with the path to the prebuilt's include directory, and will thus
    be able to find headers inside that.</p>
  </blockquote>
  
  <p>URL: <a href="http://www.srombauts.fr/android-ndk-r5b/docs/PREBUILTS.html">http://www.srombauts.fr/android-ndk-r5b/docs/PREBUILTS.html</a></p>