ldd output showing shared object file whose function is not called

Posted by iamrohitbanga on Stack Overflow See other posts from Stack Overflow or by iamrohitbanga
Published on 2010-04-16T07:07:30Z Indexed on 2010/04/16 7:13 UTC
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mpi

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thread

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linux

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ldd

I ran ldd command on an executable created by Open MPI. It shows a reference to libpthread.so Using LD_PRELOAD variable I created my own implementation of pthread_create, but from the it output it seems that MPI implementation is not calling pthread_create as I had expected. Why does ldd show pthread so file in output if it is not being used? does Open MPI not use a separate MPI thread for every node to implement the functionality?

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