Hello, I am trying to use appsrc to get data from my C application and met following problems. 1.undefined reference to `gst_app_buffer_new' 2. undefined reference to `gst_app_src_push_buffer' 3.undefined reference to gst_app_src_end_of_stream After searching for a solution, I saw someone suggest add -lgstapp-0.10 into the make file: Following is the commands in the make file. export PKG_CONFIG_PATH=/root/targetfs/opt/gstreame/lib/pkgconfig:$PKG_CONFIG_PATH /root/CodeSourcery/Sourcery_G++_Lite//bin/arm-none-linux-gnueabi-gcc -lgstapp-0.10 `pkg-config --cflags --libs gstreamer-0.10`-o syn test_syn.c And then I have following compile errors. However, i did check and found that the missing libgstbase-0.10.so.0 is in the same place with <a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>. Any suggestions? /root/CodeSourcery/Sourcery_G++_Lite/bin/../lib/gcc/arm-none-linux-gnueabi/4.3.3/../../../../arm-none-linux-gnueabi/bin/ld: warning: libgstbase-0.10.so.0, needed by /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>, not found (try using -rpath or -rpath-link) /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_sink_wait_preroll' /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_src_set_live' /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_src_get_type' /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_src_query_latency' /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_src_set_format' /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_src_is_live' /root/targetfs///opt/gstreamer/lib/<a href="http://libgstapp-0.10.so">libgstapp-0.10.so</a>: undefined reference to `gst_base_sink_get_type' Thanks, Jun