<div dir="ltr"> Hello! My goal is to use functions such as gst_app_sink_pull_sample (I am trying to run an old android application). But it gives linker errors. First of all, to check if Gstreamer and NDK are correctly configured, I run all 5 tutorials given by GStreamer and those compiled and run without any problem. GStreamer used: 1.8.0 for android / NDK: 21.0.6113669 / Android Studio: 4.0.1 So, to simplify the problem I just added that function to tutorial-1 to test if the problem comes with the linker or with the code. All the code is almost the same as the tutorial-1, with the exception of three lines (in addition of gst/app/app.h), I just added this code in the JNI_OnLoad function in tutorial-1.<code>c</code> : <pre class="gmail-default gmail-s-code-block gmail-hljs gmail-lisp"><code> GstAppSink *sink = NULL; GstSample* sample = gst_app_sink_pull_sample(sink); GstBuffer* buffer = gst_sample_get_buffer(sample);</code></pre> <div> </div><div></div><div><code> Because linker errors can happen when a library is missing, I included all of them in the Android.mk: </code></div><div><code> </code><pre class="gmail-default gmail-s-code-block gmail-hljs gmail-makefile"><code>GSTREAMER_PLUGINS := $(GSTREAMER_PLUGINS_CORE) $(GSTREAMER_PLUGINS_PLAYBACK) $(GSTREAMER_PLUGINS_CODECS) $(GSTREAMER_PLUGINS_CODECS_RESTRICTED) $(GSTREAMER_PLUGINS_NET) $(GSTREAMER_PLUGINS_SYS)</code></pre></div><div> </div><div> However, it still gives a linker error. The full stack is: </div><div> <pre class="gmail-default gmail-s-code-block gmail-hljs gmail-sql"><code>Build command failed. Error while executing process /home/tech/Android/Sdk/ndk/21.0.6113669/ndk-build with arguments {NDK_PROJECT_PATH=null APP_BUILD_SCRIPT=/home/tech/StudioProjects/gst-docs/examples/tutorials/android/android-tutorial-1/jni/Android.mk NDK_APPLICATION_MK=/home/tech/StudioProjects/gst-docs/examples/tutorials/android/android-tutorial-1/jni/Application.mk APP_ABI=armeabi-v7a NDK_ALL_ABIS=armeabi-v7a NDK_DEBUG=1 APP_PLATFORM=android-16 NDK_OUT=/home/tech/StudioProjects/gst-docs/examples/tutorials/android/android-tutorial-1/build/intermediates/ndkBuild/debug/obj NDK_LIBS_OUT=/home/tech/StudioProjects/gst-docs/examples/tutorials/android/android-tutorial-1/build/intermediates/ndkBuild/debug/lib NDK_APPLICATION_MK=jni/Application.mk GSTREAMER_JAVA_SRC_DIR=src GSTREAMER_ROOT_ANDROID=/home/tech/StudioProjects/ci_host_android/app/src/main/android_libs/gstreamer GSTREAMER_ASSETS_DIR=src/assets /home/tech/StudioProjects/gst-docs/examples/tutorials/android/android-tutorial-1/build/intermediates/ndkBuild/debug/obj/local/armeabi-v7a/libtutorial-1.so} [armeabi-v7a] Compile thumb : tutorial-1 <= tutorial-1.c GStreamer : [GEN] => gst-build-armeabi-v7a/gstreamer_android.c GStreamer : [COMPILE] => gst-build-armeabi-v7a/gstreamer_android.c GStreamer : [LINK] => gst-build-armeabi-v7a/libgstreamer_android.so Done mkdir Done cp [armeabi-v7a] Prebuilt : libgstreamer_android.so <= gst-build-armeabi-v7a/ [armeabi-v7a] SharedLibrary : libtutorial-1.so jni/tutorial-1.c:28: error: undefined reference to 'gst_app_sink_pull_sample' clang++: error: linker command failed with exit code 1 (use -v to see invocation) make: *** [/home/tech/Android/Sdk/ndk/21.0.6113669/build/core/build-<a href="http://binary.mk">binary.mk</a>:725: /home/tech/StudioProjects/gst-docs/examples/tutorials/android/android-tutorial-1/build/intermediates/ndkBuild/debug/obj/local/armeabi-v7a/libtutorial-1.so] Error 1 </code></pre><pre class="gmail-default gmail-s-code-block gmail-hljs gmail-sql"><code>Another idea was that probably those functions (gst_app_sink_*) were not in the library (libgstapp-1.0.a), so I run the command nm to know the exported functions inside the library. However, the library contains those functions, so the only possibility is that the library is not being imported. I also tested other functions (for example: get_app_stream_type_get_type) inside that library and none of those work (the functions are recognized by the headers, but not by the linker). Then, probably this is a bug or I am missing something. </code></pre><pre class="gmail-default gmail-s-code-block gmail-hljs gmail-sql"><code>Regards </code></pre><pre class="gmail-default gmail-s-code-block gmail-hljs gmail-sql"><code> </code></pre> </div></div>