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>To: address@hidden >From: Jim Barbour <address@hidden> >Subject: netcdf I/O question >Organization: NOAA/FSL >Keywords: 199611081713.AA09064 Hi Jim, > I am trying to get a sense of how NetCDF's I/O works. > > o Does is use stdio or unix I/O (open, read, write, etc.) It uses POSIX I/O, which is the standardized name for Unix I/O, except that it's supported on non-Unix systems: open, read, write, lseek, ... > o Does it typically do large os small reads? It tries to buffer I/O somewhat, by determining a preferred I/O block size. If a preferred block size isn't available, it just uses 8192 byte buffers. For more details, see the file netcdf/src/libsrc/posixio.c in the distribution of the C-language-only alpha release at ftp://ftp.unidata.ucar.edu/pub/netcdf/netcdf-3.1a.tar.Z --Russ _____________________________________________________________________ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu