Error when using python to wrap up my c++ code into *.so file

Question

I have a small project wrote in c++, and now I am going to build it into *.so file. it works fine in the building process, no errors and generate the *.so I want.

file I use for building *.so file

module1 = Extension('classmod',
        include_dirs=['/usr/lib/python2.7/dist-packages/numpy/','/home/******/OpenCV/opencv/release/include','/home/******/OpenCV/opencv/release/include/opencv','/home/******/OpenCV/opencv/release/include/opencv2','/home/******/modulepipe/eigen-eigen-b23437e61a07'],
        library_dirs=['/usr/local/lib/'],
        libraries=['opencv_calib3d','opencv_contrib','opencv_core','opencv_features2d','opencv_flann','opencv_gpu',
                           'opencv_highgui','opencv_imgproc','opencv_legacy','opencv_ml','opencv_nonfree','opencv_objdetect',
                   'opencv_photo','opencv_stitching','opencv_superres','opencv_ts','opencv_video','opencv_videostab'],
        sources=['classmodule.cpp','patch_match.cpp','compute_jaccard.cpp','find_diff.cpp','refine_match.cpp','tps.cpp','book_pipeline_single.cpp','imgfeatures.c','kdtree.c','minpq.c','sift.c','utils.c'],
                 language='c++',
             extra_compile_args=['-O3'])

setup(name='classmod',
        version='1.0',
        description='blah',
        author='blah',
        url='blah',
        ext_modules=[module1]
)

However when I am trying to load this .so lib use lbb, it tells me about can not find several opencv *.so lib.

command I use for testing:

~/CDH/modulepipe$ ldd classmod.so 
        linux-gate.so.1 =>  (0xb77b4000)
        libopencv_calib3d.so.2.4 => not found
        libopencv_core.so.2.4 => not found
        libopencv_features2d.so.2.4 => not found
        libopencv_highgui.so.2.4 => not found
        libopencv_imgproc.so.2.4 => not found
        libopencv_nonfree.so.2.4 => not found
        libstdc++.so.6 => /usr/lib/i386-linux-gnu/libstdc++.so.6 (0xb7690000)
        libm.so.6 => /lib/i386-linux-gnu/libm.so.6 (0xb7663000)
        libgcc_s.so.1 => /lib/i386-linux-gnu/libgcc_s.so.1 (0xb7645000)
        libpthread.so.0 => /lib/i386-linux-gnu/libpthread.so.0 (0xb762a000)
        libc.so.6 => /lib/i386-linux-gnu/libc.so.6 (0xb7480000)
        /lib/ld-linux.so.2 (0xb77b5000)

This is the problem I have. Can anyone help me on explaining this?

I had this "lib not found problem" before, and it was in the build phase. But in this case, in the building process it passed, which means ldd could find *.so's it needed. So how it happens that, when I am trying to run "ldd classmod.so", it could not find the *.so's.

Answer 1

Your loader can't find those shared objects. Either place them somewhere the loader expects to find them, modify the loader configuration ( man 8 ldconfig ) to look for shared objects where they are, or use one of the loader's environment variables ( man 8 ld.so ) to specify where to look for them.