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Hi Tomas, > I was looking at the C++ netCDF interface the other day > and checking my compiled libraries on the HP-UX platform > when I noticed that the example.nc files, which are generated > by the example.c and example.cc test programs in the c++ > directory of the netCDF distribution, are not identical. > I used ncdump to look at the files and they turn out > identical in the cdl format generated by ncdump. > If I run ncgen on the cdl format generated by ncdump > I get a file which is identical to the output of example.c > and 8 bytes shorter than the output of example.cc. > I send the two output files to you as a shell archive in a separate > mail message (exc.nc is generated by example.c and excc.nc is written > by example.cc) so you can have a look at this. > > Is the netCDF format not uniquely determined by the cdl > description, i.e. can there by unused parts in the netCDF > files which make files which have different sizes look > identical from the viewpoint of application programs > reading them throught the netCDF interface? > > This seems strange because I thought the c++ interface > did nothing on its own and make the c-code do all the real work. Thanks for sending this. It's a mystery to me also, but I will have to wait until the end of this week to look at it more carefully, You are corect that the C++ interface is just a thin layer over the C interface, and should produce the same file. --Russ ______________________________________________________________________________ Russ Rew UCAR Unidata Program address@hidden http://www.unidata.ucar.edu