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We have seen this before. Is your input file small enough that you send it as an attachment? > Dear NetCDF Support: > > I have an input file that I can read with my ncdump, open > with nf_open(), but which gives an error with nf_open_par(): > > Testing nf_open()... > > nf_open(): > No error > > nf_close(): > No error > > Testing nf_open_par()... > > nf_open_par(): > NetCDF: Unknown file format > > What does this mean - what is it about the file that that > allows it to be opened by nf_open() but not nf_open_par()? > I get the same error with different versions of NetCDF, > and with different versions of HDF5 (if that matters). > > Below is my test script. > > Best regards, > > Max > --- > Max R. Dechantsreiter > President > Performance Jones L.L.C. > address@hidden > > > #!/bin/sh > > cat > test_nf_open_par.F90 << EOF > program test_nf_open_par > !USE mpi, ONLY: MPI_INFO_NULL > USE mpi > INCLUDE 'netcdf.inc' > > character (len=*), parameter :: grid="iconR2B04-grid.nc" > integer :: ierr, ncid, status > > call MPI_Init(ierr) > > print '()' > > print '(a,/)', "Testing nf_open()..." > status = nf_open(grid, nf_nowrite, ncid) > print *, "nf_open(): ", nf_strerror(status) > if (status == nf_noerr) then > status = nf_close(ncid) > print *, "nf_close(): ", nf_strerror(status) > end if > > print '(a,/)', "Testing nf_open_par()..." > status = nf_open_par(grid, IOR(nf_nowrite, nf_mpiio), & > & MPI_COMM_WORLD, MPI_INFO_NULL, ncid) > print *, "nf_open_par(): ", nf_strerror(status) > if (status == nf_noerr) then > status = nf_close(ncid) > print *, "nf_close(): ", nf_strerror(status) > end if > > call MPI_Finalize(ierr) > > end program test_nf_open_par > EOF > > module purge > module load intel/2017.5.239 > module load impi/2017.4.239 > module list > > ZLIB_VERSION=1.2.11 > SZIP_VERSION=2.1.1 > HDF5_VERSION=1.10.2 > HDF5_VERSION=1.8.18 > NETCDF_C_VERSION=4.6.1 > NETCDF_FORTRAN_VERSION=4.4.4 > > LIB=/global/scratch/users/maxd/ICON/lib-avx512 > > ZLIB=$LIB/zlib-$ZLIB_VERSION > SZLIB=$LIB/szip-$SZIP_VERSION > HDF5=$LIB/phdf5-$HDF5_VERSION > NETCDF4=$LIB/netCDF4-$NETCDF_C_VERSION > > export > CPATH=$NETCDF4/include:$HDF5/include:$ZLIB/include:$SZLIB/include:$CPATH > LD_LIBRARY_PATH=$HDF5/lib:$ZLIB/lib:$SZLIB/lib:$LD_LIBRARY_PATH > LD_LIBRARY_PATH=$NETCDF4/lib:$LD_LIBRARY_PATH > LIBRARY_PATH=$LD_LIBRARY_PATH > export LD_LIBRARY_PATH # shared libraries > export LIBRARY_PATH # static libraries > > mpiifort test_nf_open_par.F90 -lnetcdff -lnetcdf -lhdf5 -lsz -lz > > mpiexec -n 1 ./a.out > > =Dennis Heimbigner Unidata Ticket Details =================== Ticket ID: GXY-620794 Department: Support netCDF Priority: Normal Status: Open =================== NOTE: All email exchanges with Unidata User Support are recorded in the Unidata inquiry tracking system and then made publicly available through the web. If you do not want to have your interactions made available in this way, you must let us know in each email you send to us.