writing large variables

[John Clyne]

Is it possible to write a large variable (>4GB) to a file with pnetcdf and read back the variable from the resulting file with netCDF? Outputting a large variable with pnetcdf appears to require passing the NC_64BIT_DATA flag (not NC_64BIT_OFFSET) to nc_create_par() - without this flag an error is generated. The file is written successfully, but when NC_64BIT_DATA is used the file is unrecognized by netcdf. For example:

yslogin2[43] ncdump -h vx.0000.nc0
ncdump: vx.0000.nc0: NetCDF: Unknown file format

From what I can gather from the web the NC_64BIT_DATA results in the generation of a CDF-5 formatted file. Is there support for CDF-5 in netCDF, or any other options for mixing pnetcdf and netCDF?

Thanks!

John Clyne
National Center for Atmospheric Research
303.497.1236 (w), 303.809.1922 (c)
clyne at ucar.edu