docs/html/sdk/ndk/index.jd

ndk=true

ndk.win_download=android-ndk-r7-windows.zip
ndk.win_bytes=81270552
ndk.win_checksum=55483482cf2b75e8dd1a5d9a7caeb6e5

ndk.mac_download=android-ndk-r7-darwin-x86.tar.bz2
ndk.mac_bytes=71262092
ndk.mac_checksum=817ca5675a1dd44078098e43070f19b6

ndk.linux_download=android-ndk-r7-linux-x86.tar.bz2
ndk.linux_bytes=64884365
ndk.linux_checksum=bf15e6b47bf50824c4b96849bf003ca3

page.title=Android NDK

@jd:body

<h2 id="notes">Revisions</h2>

<p>The sections below provide information and notes about successive releases of
the NDK, as denoted by revision number. </p>

<script type="text/javascript">
function toggleDiv(link) {
  var toggleable = $(link).parent();
  if (toggleable.hasClass("closed")) {
    //$(".toggleme", toggleable).slideDown("fast");
    toggleable.removeClass("closed");
    toggleable.addClass("open");
    $(".toggle-img", toggleable).attr("title", "hide").attr("src", "{@docRoot}assets/images/triangle-opened.png");
  } else {
    //$(".toggleme", toggleable).slideUp("fast");
    toggleable.removeClass("open");
    toggleable.addClass("closed");
    $(".toggle-img", toggleable).attr("title", "show").attr("src", "/assets/images/triangle-closed.png");
  }
  return false;
}
</script>
<style>
.toggleable {
padding: .25em 1em;
}
.toggleme {
  padding: 1em 1em 0 2em;
  line-height:1em;
}
.toggleable a {
  text-decoration:none;
}
.toggleme a {
  text-decoration:underline;
}
.toggleable.closed .toggleme {
  display:none;}
#jd-content .toggle-img {
  margin:0;
}
</style>

<div class="toggleable open">
  <a href="#" onclick="return toggleDiv(this)"><img src=
  "{@docRoot}assets/images/triangle-opened.png" class="toggle-img" height="9px" width="9px">
  Android NDK, Revision 7</a> <em>(November 2011)</em>

  <div class="toggleme">
    <p>This release of the NDK includes new features to support the Android 4.0 platform as well
    as many other additions and improvements:</p>

    <dl>
      <dt>New features</dt>

      <dd>
        <ul>
          <li>Added official NDK APIs for Android 4.0 (API level 14), which adds the following
          native features to the platform:

            <ul>
              <li>Added native multimedia API based on the Khronos Group OpenMAX AL™ 1.0.1
              standard. The new <code>&lt;OMXAL/OpenMAXAL.h&gt;</code> and
              <code>&lt;OMXAL/OpenMAXAL_Android.h&gt;</code> headers allow applications targeting
              API level 14 to perform multimedia output directly from native code by using a new
              Android-specific buffer queue interface. For more details, see
              <code>docs/openmaxal/index.html</code> and <a href=
              "http://www.khronos.org/openmax/">http://www.khronos.org/openmax/</a>.</li>

              <li>Updated the native audio API based on the Khronos Group OpenSL ES 1.0.1™
              standard. With API Level 14, you can now decode compressed audio (e.g. MP3, AAC,
              Vorbis) to PCM. For more details, see <code>docs/opensles/index.html</code> and
              <a href=
              "http://www.khronos.org/opensles">http://www.khronos.org/opensles/</a>.</li>
            </ul>
          </li>

          <li>Added CCache support. To speed up large rebuilds, define the
          <code>NDK_CCACHE</code> environment variable to <code>ccache</code> (or the path to
          your <code>ccache</code> binary). When declared, the NDK build system automatically
          uses CCache when compiling any source file. For example:
            <pre>
export NDK_CCACHE=ccache
</pre>
          <p class="note"><strong>Note:</strong> CCache is not included in the NDK release
          so you must have it installed prior to using it. For more information about CCache, see
          <a href="http://ccache.samba.org">http://ccache.samba.org</a>.</p>
          </li>

          <li>Added support for setting <code>APP_ABI</code> to <code>all</code> to indicate that
          you want to build your NDK modules for all the ABIs supported by your given NDK
          release. This means that either one of the following two lines in your
          <code>Application.mk</code> are equivalent with this release:
            <pre>
APP_ABI := all
APP_ABI := armeabi armeabi-v7a x86
</pre>

            <p>This also works if you define <code>APP_ABI</code> when calling
            <code>ndk-build</code> from the command-line, which is a quick way to check that your
            project builds for all supported ABIs without changing the project's
            <code>Application.mk file</code>. For example:</p>
            <pre>
ndk-build APP_ABI=all
</pre>
          </li>

          <li>Added a <code>LOCAL_CPP_FEATURES</code> variable in <code>Android.mk</code> that
          allows you to declare which C++ features (RTTI or Exceptions) your module uses. This
          ensures that the final linking works correctly if you have prebuilt modules that depend
          on these features. See <code>docs/ANDROID-MK.html</code> and
          <code>docs/CPLUSPLUS-SUPPORT.html</code> for more details.</li>

          <li>Shortened paths to source and object files that are used in build commands. When
          invoking <code>$NDK/ndk-build</code> from your project path, the paths to the source,
          object, and binary files that are passed to the build commands are significantly
          shorter now, because they are passed relative to the current directory. This is useful
          when building projects with a lot of source files, to avoid limits on the maximum
          command line length supported by your host operating system. The behavior is unchanged
          if you invoke <code>ndk-build</code> from a sub-directory of your project tree, or if
          you define <code>NDK_PROJECT_PATH</code> to point to a specific directory.</li>
        </ul>
      </dd>

      <dt>Experimental features</dt>

      <dd>
        You can now build your NDK source files on Windows <em>without</em> Cygwin by calling the
        <code>ndk-build.cmd</code> script from the command line from your project path. The
        script takes exactly the same arguments as the original <code>ndk-build</code> script.
        The Windows NDK package comes with its own prebuilt binaries for GNU Make, Awk and other
        tools required by the build. You should not need to install anything else to get a
        working build system.

        <p class="caution"><strong>Important:</strong> <code>ndk-gdb</code> does not work on
        Windows, so you still need Cygwin to debug.</p>

        <p>This feature is still experimental, so feel free to try it and report issues on the
        <a href="http://b.android.com">public bug database</a> or <a href=
        "http://groups.google.com/group/android-ndk">public forum</a>. All samples and unit tests
        shipped with the NDK succesfully compile with this feature.</p>
      </dd>

      <dt>Important bug fixes</dt>

      <dd>
        <ul>
          <li>Imported shared libraries are now installed by default to the target installation
          location (<code>libs/&lt;abi&gt;</code>) if <code>APP_MODULES</code> is not defined in
          your <code>Application.mk</code>. For example, if a top-level module <code>foo</code>
          imports a module <code>bar</code>, then both <code>libfoo.so</code> and
          <code>libbar.so</code> are copied to the install location. Previously, only
          <code>libfoo.so</code> was copied, unless you listed <code>bar</code> in your
          <code>APP_MODULES</code> too. If you define <code>APP_MODULES</code> explicitly, the
          behavior is unchanged.</li>

          <li><code>ndk-gdb</code> now works correctly for activities with multiple categories in
          their MAIN intent filters.</li>

          <li>Static library imports are now properly transitive. For example, if a top-level
          module <code>foo</code> imports static library <code>bar</code> that imports static
          library <code>zoo</code>, the <code>libfoo.so</code> will now be linked against both
          <code>libbar.a</code> and <code>libzoo.a</code>.</li>
        </ul>
      </dd>

      <dt>Other changes</dt>

      <dd>
        <ul>
          <li><code>docs/NATIVE-ACTIVITY.HTML</code>: Fixed typo. The minimum API level should be
          9, not 8 for native activities.</li>

          <li><code>docs/STABLE-APIS.html</code>: Added missing documentation listing EGL as a
          supported stable API, starting from API level 9.</li>

          <li><code>download-toolchain-sources.sh</code>: Updated to download the toolchain
          sources from <a href="http://android.googlesource.com">android.googlesource.com</a>,
          which is the new location for the AOSP servers.</li>

          <li>Added a new C++ support runtime named <code>gabi++</code>. More details about it
          are available in the updated <code>docs/CPLUSPLUS-SUPPORT.html</code>.</li>

          <li>Added a new C++ support runtime named <code>gnustl_shared</code> that corresponds
          to the shared library version of GNU libstdc++ v3 (GPLv3 license). See more info at
          <code>docs/CPLUSPLUS-SUPPORT.html</code></li>

          <li>Added support for RTTI in the STLport C++ runtimes (no support for
          exceptions).</li>

          <li>Added support for multiple file extensions in <code>LOCAL_CPP_EXTENSION</code>. For
          example, to compile both <code>foo.cpp</code> and <code>bar.cxx</code> as C++ sources,
          declare the following:
            <pre>
LOCAL_CPP_EXTENSION := .cpp .cxx
</pre>
          </li>

          <li>Removed many unwanted exported symbols from the link-time shared system libraries
          provided by the NDK. This ensures that code generated with the standalone toolchain
          doesn't risk to accidentally depend on a non-stable ABI symbol (e.g. any libgcc.a
          symbol that changes each time the toolchain used to build the platform is changed)</li>

          <li>Refreshed the EGL and OpenGLES Khronos headers to support more extensions. Note
          that this does <em>not</em> change the NDK ABIs for the corresponding libraries,
          because each extension must be probed at runtime by the client application.

            <p>The extensions that are available depend on your actual device and GPU drivers,
            not the platform version the device runs on. The header changes simply add new
            constants and types to make it easier to use the extensions when they have been
            probed with <code>eglGetProcAddress()</code> or <code>glGetProcAddress()</code>. The
            following list describes the newly supported extensions:</p>

            <dl>
              <dt>GLES 1.x</dt>

              <dd>
                <ul>
                  <li><code>GL_OES_vertex_array_object</code></li>

                  <li><code>GL_OES_EGL_image_external</code></li>

                  <li><code>GL_APPLE_texture_2D_limited_npot</code></li>

                  <li><code>GL_EXT_blend_minmax</code></li>

                  <li><code>GL_EXT_discard_framebuffer</code></li>

                  <li><code>GL_EXT_multi_draw_arrays</code></li>

                  <li><code>GL_EXT_read_format_bgra</code></li>

                  <li><code>GL_EXT_texture_filter_anisotropic</code></li>

                  <li><code>GL_EXT_texture_format_BGRA8888</code></li>

                  <li><code>GL_EXT_texture_lod_bias</code></li>

                  <li><code>GL_IMG_read_format</code></li>

                  <li><code>GL_IMG_texture_compression_pvrtc</code></li>

                  <li><code>GL_IMG_texture_env_enhanced_fixed_function</code></li>

                  <li><code>GL_IMG_user_clip_plane</code></li>

                  <li><code>GL_IMG_multisampled_render_to_texture</code></li>

                  <li><code>GL_NV_fence</code></li>

                  <li><code>GL_QCOM_driver_control</code></li>

                  <li><code>GL_QCOM_extended_get</code></li>

                  <li><code>GL_QCOM_extended_get2</code></li>

                  <li><code>GL_QCOM_perfmon_global_mode</code></li>

                  <li><code>GL_QCOM_writeonly_rendering</code></li>

                  <li><code>GL_QCOM_tiled_rendering</code></li>
                </ul>
              </dd>

              <dt>GLES 2.0</dt>

              <dd>
                <ul>
                  <li><code>GL_OES_element_index_uint</code></li>

                  <li><code>GL_OES_get_program_binary</code></li>

                  <li><code>GL_OES_mapbuffer</code></li>

                  <li><code>GL_OES_packed_depth_stencil</code></li>

                  <li><code>GL_OES_texture_3D</code></li>

                  <li><code>GL_OES_texture_float</code></li>

                  <li><code>GL_OES_texture_float_linear</code></li>

                  <li><code>GL_OES_texture_half_float_linear</code></li>

                  <li><code>GL_OES_texture_npot</code></li>

                  <li><code>GL_OES_vertex_array_object</code></li>

                  <li><code>GL_OES_EGL_image_external</code></li>

                  <li><code>GL_AMD_program_binary_Z400</code></li>

                  <li><code>GL_EXT_blend_minmax</code></li>

                  <li><code>GL_EXT_discard_framebuffer</code></li>

                  <li><code>GL_EXT_multi_draw_arrays</code></li>

                  <li><code>GL_EXT_read_format_bgra</code></li>

                  <li><code>GL_EXT_texture_format_BGRA8888</code></li>

                  <li><code>GL_EXT_texture_compression_dxt1</code></li>

                  <li><code>GL_IMG_program_binary</code></li>

                  <li><code>GL_IMG_read_format</code></li>

                  <li><code>GL_IMG_shader_binary</code></li>

                  <li><code>GL_IMG_texture_compression_pvrtc</code></li>

                  <li><code>GL_IMG_multisampled_render_to_texture</code></li>

                  <li><code>GL_NV_coverage_sample</code></li>

                  <li><code>GL_NV_depth_nonlinear</code></li>

                  <li><code>GL_QCOM_extended_get</code></li>

                  <li><code>GL_QCOM_extended_get2</code></li>

                  <li><code>GL_QCOM_writeonly_rendering</code></li>

                  <li><code>GL_QCOM_tiled_rendering</code></li>
                </ul>
              </dd>

              <dt>EGL</dt>

              <dd>
                <ul>
                  <li><code>EGL_ANDROID_recordable</code></li>

                  <li><code>EGL_NV_system_time</code></li>
                </ul>
              </dd>
            </dl>
          </li>
        </ul>
      </dd>
    </dl>
  </div>
</div>



<div class="toggleable closed">
  <a href="#" onclick="return toggleDiv(this)"><img src=
  "{@docRoot}assets/images/triangle-closed.png" class="toggle-img" height="9px" width="9px">
  Android NDK, Revision 6b</a> <em>(August 2011)</em>

   <div class="toggleme">
      <p>This release of the NDK does not include any new features compared to r6. The r6b release
      addresses the following issues in the r6 release:</p>
      <dl>
        <dt>Important bug fixes</dt>
        <dd>
          <ul>
            <li>Fixed the build when <code>APP_ABI="armeabi x86"</code> is used for
            multi-architecture builds.</li>
            <li>Fixed the location of prebuilt STLport binaries in the NDK release package.
            A bug in the packaging script placed them in the wrong location.</li>
            <li>Fixed <code>atexit()</code> usage in shared libraries with the x86standalone
            toolchain.</li>
            <li>Fixed <code>make-standalone-toolchain.sh --arch=x86</code>. It used to fail
            to copy the proper GNU libstdc++ binaries to the right location.</li>
            <li>Fixed the standalone toolchain linker warnings about missing the definition and
            size for the <code>__dso_handle</code> symbol (ARM only).</li>
            <li>Fixed the inclusion order of <code>$(SYSROOT)/usr/include</code> for x86 builds.
            See the <a href="http://code.google.com/p/android/issues/detail?id=18540">bug</a> for
            more information.</li>
            <li>Fixed the definitions of <code>ptrdiff_t</code> and <code>size_t</code> in
            x86-specific systems when they are used with the x86 standalone toolchain.</li>
          </ul>
        </dd>
      </dl>
  </div>
</div>

<div class="toggleable closed">
  <a href="#" onclick="return toggleDiv(this)"><img src=
  "{@docRoot}assets/images/triangle-closed.png" class="toggle-img" height="9px" width="9px">
  Android NDK, Revision 6</a> <em>(July 2011)</em>

   <div class="toggleme">
      <p>This release of the NDK includes support for the x86 ABI and other minor changes.
      For detailed information describing the changes in this release, read the
      <code>CHANGES.HTML</code> document included in the NDK package.
      </p>
      <dl>
        <dt>General notes:</dt>
        <dd>
          <ul>
            <li>Adds support for the x86 ABI, which allows you to generate machine code
            that runs on compatible x86-based Android devices. Major features for x86
            include x86-specific toolchains, system headers, libraries and
            debugging support. For all of the details regarding x86 support,
            see <code>docs/CPU-X86.html</code> in the NDK package.

              <p>By default, code is generated for ARM-based devices, but you can add x86 to your
              <code>APP_ABI</code> definition in your <code>Application.mk</code> file to build
              for x86 platforms. For example, the following line instructs <code>ndk-build</code>
              to build your code for three distinct ABIs:</p>

              <pre>APP_ABI := armeabi armeabi-v7a x86</pre>

              <p>Unless you rely on ARM-based assembly sources, you shouldn't need to touch
              your <code>Android.mk</code> files to build x86 machine code.</p>

            </li>

            <li>You can build a standalone x86 toolchain using the <code>--toolchain=x86-4.4.3</code>
            option when calling <code>make-standalone-toolchain.sh</code>. See
            <code>docs/STANDALONE-TOOLCHAIN.html</code> for more details.
            </li>
            <li>The new <code>ndk-stack</code> tool lets you translate stack traces in
            <code>logcat</code> that are generated by native code. The tool translates
            instruction addresses into a readable format that contains things such
            as the function, source file, and line number corresponding to each stack frame.
            For more information and a usage example, see <code>docs/NDK-STACK.html</code>.
            </li>
          </ul>
        </dd>
        <dt>Other changes:</dt>
        <dd><code>arm-eabi-4.4.0</code>, which had been deprecated since NDK r5, has been
        removed from the NDK distribution.</dd>

      </dl>
    </div>
  </div>

<div class="toggleable closed">
  <a href="#" onclick="return toggleDiv(this)"><img src=
  "{@docRoot}assets/images/triangle-closed.png" class="toggle-img" height="9px" width="9px">
  Android NDK, Revision 5c</a> <em>(June 2011)</em>

  <div class="toggleme">
    <p>This release of the NDK does not include any new features compared to r5b. The r5c release
    addresses the following problems in the r5b release:</p>
    <dl>
      <dt>Important bug fixes:</dt>
      <dd>
        <ul>
          <li><code>ndk-build</code>: Fixed a rare bug that appeared when trying to perform parallel
          builds of debuggable projects.</li>

          <li>Fixed a typo that prevented <code>LOCAL_WHOLE_STATIC_LIBRARIES</code> to work
          correctly with the new toolchain and added documentation for this in
          <code>docs/ANDROID-MK.html</code>.</li>

          <li>Fixed a bug where code linked against <code>gnustl_static</code> crashed when run on
          platform releases older than API level 8 (Android 2.2).</li>

          <li><code>ndk-gdb</code>: Fixed a bug that caused a segmentation fault when debugging Android 3.0
          or newer devices.</li>

          <li><code>&lt;android/input.h&gt;</code>: Two functions that were introduced in API level
          9 (Android 2.3) were incorrect and are fixed. While this breaks the source API, the
          binary interface to the system is unchanged. The incorrect functions were missing a
          <code>history_index</code> parameter, and the correct definitions are shown below:
<pre>
float AMotionEvent_getHistoricalRawX(const AInputEvent* motion_event,
                                           size_t pointer_index,
                                           size_t history_index);

float AMotionEvent_getHistoricalRawY(const AInputEvent* motion_event,
                                           size_t pointer_index,
                                           size_t history_index);
</pre>
          </li>

          <li>Updated the C library ARM binary for API level 9 (Android 2.3) to correctly expose at
          link time new functions that were added in that API level (for example,
          <code>pthread_rwlock_init</code>).</li>

        </ul>
      </dd>

      <dt>Minor improvements and fixes:</dt>
      <dd>
        <ul>
          <li>Object files are now always linked in the order they appear in
          <code>LOCAL_SRC_FILES</code>. This was not the case previously because the files were
          grouped by source extensions instead.</li>

          <li>When <code>import-module</code> fails, it now prints the list of directories that
          were searched. This is useful to check that the <code>NDK_MODULE_PATH</code> definition
          used by the build system is correct.</li>

          <li>When <code>import-module</code> succeeds, it now prints the directory where the
          module was found to the log (visible with <code>NDK_LOG=1</code>).</li>

          <li>Increased the build speed of debuggable applications when there is a very large number
          of include directories in the project.</li>

          <li><code>ndk-gdb</code>: Better detection of <code>adb shell</code> failures and improved
          error messages.</li>

          <li><code>&lt;pthread.h&gt;</code>: Fixed the definition of
          <code>PTHREAD_RWLOCK_INITIALIZER</code> for API level 9 (Android 2.3) and higher.</li>

          <li>Fixed an issue where a module could import itself, resulting in an infinite loop in
          GNU Make.</li>

          <li>Fixed a bug that caused the build to fail if <code>LOCAL_ARM_NEON</code> was set to
          true (typo in <code>build/core/build-binary.mk</code>).</li>

          <li>Fixed a bug that prevented the compilation of </code>.s</code> assembly files
          (<code>.S</code> files were okay).</li>
        </ul>
      </dd>
  </div>
</div>

<div class="toggleable closed">
    <a href="#"
         onclick="return toggleDiv(this)"><img src="{@docRoot}assets/images/triangle-closed.png"
         class="toggle-img"
         height="9px"
         width="9px" /> Android NDK, Revision 5b</a> <em>(January 2011)</em>

    <div class="toggleme">
      <p>This release of the NDK does not include any new features compared to r5. The r5b release addresses the
      following problems in the r5 release:
      </p>
      <ul>
    <li>The r5 binaries required glibc 2.11, but the r5b binaries are generated with a special
    toolchain that targets glibc 2.7 or higher instead. The Linux toolchain binaries now run on Ubuntu 8.04 or higher. </li>
    <li>Fixes a compiler bug in the arm-linux-androideabi-4.4.3 toolchain.
    The previous binary generated invalid thumb instruction sequences when
    dealing with signed chars.</li>
    <li>Adds missing documentation for the
    "gnustl_static" value for APP_STL, that allows you to link against
    a static library version of GNU libstdc++. </li>
    <li>The following <code>ndk-build</code> issues are fixed:
      <ul>
        <li>A bug that created inconsistent dependency files when a
        compilation error occured on Windows. This prevented a proper build after
        the error was fixed in the source code.</li>
        <li>A Cygwin-specific bug where using very short paths for
        the Android NDK installation or the project path led to the
        generation of invalid dependency files. This made incremental builds
        impossible.</li>
        <li>A typo that prevented the cpufeatures library from working correctly
        with the new NDK toolchain.</li>
        <li>Builds in Cygwin are faster by avoiding calls to <code>cygpath -m</code>
        from GNU Make for every source or object file, which caused problems
        with very large source trees. In case this doesn't work properly, define <code>NDK_USE_CYGPATH=1</code> in your
        environment to use <code>cygpath -m</code> again.</li>
        <li>The Cygwin installation now notifies the user of invalid installation paths that contain spaces. Previously, an invalid path
        would output an error that complained about an incorrect version of GNU Make, even if the right one was installed.
      </ul>
    </li>
  <li>Fixed a typo that prevented the <code>NDK_MODULE_PATH</code> environment variable from working properly when
  it contained multiple directories separated with a colon. </li>
  <li>The <code>prebuilt-common.sh</code> script contains fixes to check the compiler for 64-bit
  generated machine code, instead of relying on the host tag, which
  allows the 32-bit toolchain to rebuild properly on Snow Leopard. The toolchain rebuild scripts now also support
  using a 32-bit host toolchain.</li>
  <li>A missing declaration for <code>INET_ADDRSTRLEN</code> was added to <code>&lt;netinet/in.h&gt;</code>.</li>
  <li>Missing declarations for <code>IN6_IS_ADDR_MC_NODELOCAL</code> and <code>IN6_IS_ADDR_MC_GLOBAL</code> were added to <code>&lt;netinet/in6.h&gt;</code>.</li>
  <li>'asm' was replaced with '__asm__' in <code>&lt;asm/byteorder.h&gt;</code> to allow compilation with <code>-std=c99</code>.</li>
  </ul>
  </div>
  </div>

<div class="toggleable closed">
    <a href="#"
         onclick="return toggleDiv(this)"><img src="{@docRoot}assets/images/triangle-closed.png"
         class="toggle-img"
         height="9px"
         width="9px" /> Android NDK, Revision 5</a> <em>(December 2010)</em>

    <div class="toggleme">
      <p>This release of the NDK includes many new APIs, most of which are introduced to
         support the development of games and similar applications that make extensive use
         of native code. Using the APIs, developers have direct native access to events, audio,
         graphics and window management, assets, and storage. Developers can also implement the
         Android application lifecycle in native code with help from the new
         {@link android.app.NativeActivity} class. For detailed information describing the changes in this
         release, read the <code>CHANGES.HTML</code> document included in the downloaded NDK package.
      </p>
      <dl>
        <dt>General notes:</dt>
        <dd>
          <ul>
            <li>Adds support for native activities, which allows you to implement the
            Android application lifecycle in native code.</li>

            <li>Adds native support for the following:

              <ul>

                <li>Input subsystem (such as the keyboard and touch screen)</li>

                <li>Access to sensor data (accelerometer, compass, gyroscope, etc).</li>

                <li>Event loop APIs to wait for things such as input and sensor events.</li>

                <li>Window and surface subsystem</li>

                <li>Audio APIs based on the OpenSL ES standard that support playback and recording
                as well as control over platform audio effects</li>

                <li>Access to assets packaged in an <code>.apk</code> file.</li>
                
              </ul>
            </li>

            <li>Includes a new toolchain (based on GCC 4.4.3), which generates better code, and can also now
            be used as a standalone cross-compiler, for people who want to build their stuff with
            <code>./configure &amp;&amp; make</code>. See
            docs/STANDALONE-TOOLCHAIN.html for the details. The binaries for GCC 4.4.0 are still provided,
            but the 4.2.1 binaries were removed.</li>

            <li>Adds support for prebuilt static and shared libraries (docs/PREBUILTS.html) and module
            exports and imports to make sharing and reuse of third-party modules much easier
            (docs/IMPORT-MODULE.html explains why).</li>

            <li>Provides a default C++ STL implementation (based on STLport) as a helper module. It can be used either
            as a static or shared library (details and usage examples are in sources/android/stlport/README). Prebuilt
            binaries for STLport (static or shared) and GNU libstdc++ (static only) are also provided if you choose to
            compile against those libraries instead of the default C++ STL implementation. 
            C++ Exceptions and RTTI are not supported in the default STL implementation. For more information, see
            docs/CPLUSPLUS-SUPPORT.HTML.</li>

            <li>Includes improvements to the <code>cpufeatures</code> helper library that improves reporting
            of the CPU type (some devices previously reported ARMv7 CPU when the device really was an ARMv6). We
            recommend developers that use this library to rebuild their applications then
            upload to Market to benefit from the improvements.</li>

            <li>Adds an EGL library that lets you create and manage OpenGL ES textures and
              services.</li>
                
            <li>Adds new sample applications, <code>native-plasma</code> and <code>native-activity</code>, 
            to demonstrate how to write a native activity.</li>

            <li>Includes many bugfixes and other small improvements; see docs/CHANGES.html for a more
              detailed list of changes.</li>
          </ul>
        </dd>
      </dl>
    </div>
  </div>

  <div class="toggleable closed">
    <a href="#"
         onclick="return toggleDiv(this)"><img src="{@docRoot}assets/images/triangle-closed.png"
         class="toggle-img"
         height="9px"
         width="9px" /> Android NDK, Revision 4b</a> <em>(June 2010)</em>

    <div class="toggleme">
      <dl>
        <dt>NDK r4b notes:</dt>

        <dd>
          <p>Includes fixes for several issues in the NDK build and debugging scripts &mdash; if
          you are using NDK r4, we recommend downloading the NDK r4b build. For detailed
          information describing the changes in this release, read the CHANGES.TXT document
          included in the downloaded NDK package.</p>
        </dd>
      </dl>

      <dl>
        <dt>General notes:</dt>

        <dd>
          <ul>
            <li>Provides a simplified build system through the new <code>ndk-build</code> build
            command.</li>

            <li>Adds support for easy native debugging of generated machine code on production
            devices through the new <code>ndk-gdb</code> command.</li>

            <li>Adds a new Android-specific ABI for ARM-based CPU architectures,
            <code>armeabi-v7a</code>. The new ABI extends the existing <code>armeabi</code> ABI to
            include these CPU instruction set extensions:

              <ul>
                <li>Thumb-2 instructions</li>

                <li>VFP hardware FPU instructions (VFPv3-D16)</li>

                <li>Optional support for ARM Advanced SIMD (NEON) GCC intrinsics and VFPv3-D32.
                Supported by devices such as Verizon Droid by Motorola, Google Nexus One, and
                others.</li>
              </ul>
            </li>

            <li>Adds a new <code>cpufeatures</code> static library (with sources) that lets your
            app detect the host device's CPU features at runtime. Specifically, applications can
            check for ARMv7-A support, as well as VFPv3-D32 and NEON support, then provide separate
            code paths as needed.</li>

            <li>Adds a sample application, <code>hello-neon</code>, that illustrates how to use the
            <code>cpufeatures</code> library to check CPU features and then provide an optimized
            code path using NEON instrinsics, if supported by the CPU.</li>

            <li>Lets you generate machine code for either or both of the instruction sets supported
            by the NDK. For example, you can build for both ARMv5 and ARMv7-A architectures at the
            same time and have everything stored to your application's final
            <code>.apk</code>.</li>

            <li>To ensure that your applications are available to users only if their devices are
            capable of running them, Android Market now filters applications based on the
            instruction set information included in your application &mdash; no action is needed on
            your part to enable the filtering. Additionally, the Android system itself also checks
            your application at install time and allows the installation to continue only if the
            application provides a library that is compiled for the device's CPU architecture.</li>

            <li>Adds support for Android 2.2, including a new stable API for accessing the pixel
            buffers of {@link android.graphics.Bitmap} objects from native code.</li>
          </ul>
        </dd>
      </dl>
    </div>
  </div>

  <div class="toggleable closed">
    <a href="#"
         onclick="return toggleDiv(this)"><img src="{@docRoot}assets/images/triangle-closed.png"
         class="toggle-img"
         height="9px"
         width="9px" /> Android NDK, Revision 3</a> <em>(March 2010)</em>

    <div class="toggleme">
      <dl>
        <dt>General notes:</dt>

        <dd>
          <ul>
            <li>Adds OpenGL ES 2.0 native library support.</li>

            <li>Adds a sample application,<code>hello-gl2</code>, that illustrates the use of
            OpenGL ES 2.0 vertex and fragment shaders.</li>

            <li>The toolchain binaries have been refreshed for this release with GCC 4.4.0, which
            should generate slightly more compact and efficient machine code than the previous one
            (4.2.1). The NDK also still provides the 4.2.1 binaries, which you can optionally use
            to build your machine code.</li>
          </ul>
        </dd>
      </dl>
    </div>
  </div>

  <div class="toggleable closed">
    <a href="#"
         onclick="return toggleDiv(this)"><img src="{@docRoot}assets/images/triangle-closed.png"
         class="toggle-img"
         height="9px"
         width="9px" /> Android NDK, Revision 2</a> <em>(September 2009)</em>

    <div class="toggleme">
      <p>Originally released as "Android 1.6 NDK, Release 1".</p>

      <dl>
        <dt>General notes:</dt>

        <dd>
          <ul>
            <li>Adds OpenGL ES 1.1 native library support.</li>

            <li>Adds a sample application, <code>san-angeles</code>, that renders 3D graphics
            through the native OpenGL ES APIs, while managing activity lifecycle with a {@link
            android.opengl.GLSurfaceView} object.</li>
          </ul>
        </dd>
      </dl>
    </div>
  </div>

  <div class="toggleable closed">
    <a href="#"
         onclick="return toggleDiv(this)"><img src="{@docRoot}assets/images/triangle-closed.png"
         class="toggle-img"
         height="9px"
         width="9px" /> Android NDK, Revision 1</a> <em>(June 2009)</em>

    <div class="toggleme">
      <p>Originally released as "Android 1.5 NDK, Release 1".</p>

      <dl>
        <dt>General notes:</dt>

        <dd>
          <ul>
            <li>Includes compiler support (GCC) for ARMv5TE instructions, including Thumb-1
            instructions.</li>

            <li>Includes system headers for stable native APIs, documentation, and sample
            applications.</li>
          </ul>
        </dd>
      </dl>
    </div>
  </div>
  
  <h2 id="installing">Installing the NDK</h2>
  <p>Installing the NDK on your development computer is straightforward and involves extracting the
  NDK from its download package.</p>

  <p>Before you get started make sure that you have downloaded the latest <a href=
  "{@docRoot}sdk/index.html">Android SDK</a> and upgraded your applications and environment as
  needed. The NDK is compatible with older platform versions but not older versions of the SDK tools.
  Also, take a moment to review the <a href="{@docRoot}sdk/ndk/overview.html#reqs">System and
Software Requirements</a>
  for the NDK, if you haven't already.</p>

  <p>To install the NDK, follow these steps:</p>

  <ol>
    <li>From the table at the top of this page, select the NDK package that is appropriate for your
    development computer and download the package.</li>

    <li>Uncompress the NDK download package using tools available on your computer. When
    uncompressed, the NDK files are contained in a directory called
    <code>android-ndk-&lt;version&gt;</code>. You can rename the NDK directory if necessary and you
    can move it to any location on your computer. This documentation refers to the NDK directory as
    <code>&lt;ndk&gt;</code>.</li>
  </ol>

  <p>You are now ready to start working with the NDK.</p>

  <h2 id="gettingstarted">Getting Started with the NDK</h2>

  <p>Once you've installed the NDK successfully, take a few minutes to read the documentation
  included in the NDK. You can find the documentation in the <code>&lt;ndk&gt;/docs/</code>
  directory. In particular, please read the OVERVIEW.HTML document completely, so that you
  understand the intent of the NDK and how to use it.</p>

  <p>If you used a previous version of the NDK, take a moment to review the list of NDK changes in
  the CHANGES.HTML document.</p>

  <p>Here's the general outline of how you work with the NDK tools:</p>

  <ol>
    <li>Place your native sources under <code>&lt;project&gt;/jni/...</code></li>

    <li>Create <code>&lt;project&gt;/jni/Android.mk</code> to describe your native sources to the
    NDK build system</li>

    <li>Optional: Create <code>&lt;project&gt;/jni/Application.mk</code>.</li>

    <li>Build your native code by running the 'ndk-build' script from your project's directory. It
    is located in the top-level NDK directory:
      <pre class="no-pretty-print">cd &lt;project&gt;
&lt;ndk&gt;/ndk-build
</pre>

      <p>The build tools copy the stripped, shared libraries needed by your application to the
      proper location in the application's project directory.</p>
    </li>

    <li>Finally, compile your application using the SDK tools in the usual way. The SDK build tools
    will package the shared libraries in the application's deployable <code>.apk</code> file.</li>
  </ol>

  <p>For complete information on all of the steps listed above, please see the documentation
  included with the NDK package.</p>

  <h2 id="samples">Sample Applications</h2>

  <p>The NDK includes sample Android applications that illustrate how to use native code in your
  Android applications. For more information, see <a href=
  "{@docRoot}sdk/ndk/overview.html#samples">Sample Applications</a>.</p>

  <h2 id="forum">Discussion Forum and Mailing List</h2>

  <p>If you have questions about the NDK or would like to read or contribute to discussions about
  it, please visit the <a href="http://groups.google.com/group/android-ndk">android-ndk</a> group
  and mailing list.</p>