ncgen [-b] [-c] [-f] [-n] [-o output_file]
input_fileWhere:
-b   Create a (binary) netCDF file.  If the -o 
option is absent,  a default file name will be constructed from the
          netCDF name (specified after the netcdf keyword in  the
          input) by appending the .nc extension.  If a file
already exists  with  the  specified  name,  it  will  be
          overwritten.
-c   Generate C source code that will create a  netCDF
file
          matching  the  netCDF specification.  The C source code
          is written to standard output.
-f   Generate Fortran source code that will create a
netCDF
          file  matching  the  netCDF specification.  The Fortran
          source code is written to standard output.     
-o
outputfile
-b option.  (This
option is
          necessary  because  netCDF  files  cannot  be   written
          directly  to  standard output, since standard output is
          not seekable.)
-n   Like -b option, except creates netCDF
file with the obsolete .cdf extension instead of the
.nc extension,
          in the absence of an output filename specified  by  the
          -O  option.  This option is only supported for
backward
          compatibility.
foo.cdl:
ncgen foo.cdl
foo.cdl, generate an  equivalent  binary
     netCDF file named x.nc:
ncgen -o x.nc foo.cdl
foo.cdl, generate a C program containing
     the  netCDF  function  invocations  necessary  to  create an
     equivalent binary netCDF file named x.nc:
ncgen -c -o x.nc foo.cdl