R developers: I have some parallel C code, written with the MPI library, that I would like to call from R, but I get the error message below. cocite.mat.true.parallel.so compiles without complaint and I have MPI in my path, but R isn't recognizing one of the MPI symbols. I have a feeling that this is going to be tricky, but I need to get this to work. Helpful suggestions? I'd be happy to share more of my R and C code if that is helpful, but I wanted to avoid a very long post at this point. Thanks, Mark > dyn.load(x = c.code, local = TRUE, now = TRUE) Error in dyn.load(x = c.code, local = TRUE, now = TRUE) : unable to load shared library '/N/u/mkimpel/BigRed/my_C/R.shared.so/cocite.mat.true.parallel.so': /N/u/mkimpel/BigRed/my_C/R.shared.so/cocite.mat.true.parallel.so: undefined symbol: ompi_mpi_comm_world > sessionInfo() R version 2.7.0 Under development (unstable) (2008-01-05 r43880) powerpc64-unknown-linux-gnu locale: LC_CTYPE=en_US.UTF-8;LC_NUMERIC=C;LC_TIME=en_US.UTF-8;LC_COLLATE=en_US.UTF-8;LC_MONETARY=en_US.UTF-8;LC_MESSAGES=en_US.UTF-8;LC_PAPER=en_US.UTF-8;LC_NAME=C;LC_ADDRESS=C;LC_TELEPHONE=C;LC_MEASUREMENT=en_US.UTF-8;LC_IDENTIFICATION=C attached base packages: [1] stats graphics grDevices utils datasets methods base > -- Mark W. Kimpel MD ** Neuroinformatics ** Dept. of Psychiatry Indiana University School of Medicine 15032 Hunter Court, Westfield, IN 46074 (317) 490-5129 Work, & Mobile & VoiceMail (317) 204-4202 Home (no voice mail please) mwkimpel<at>gmail<dot>com