NetCDF Users Guide  v1.1
Deprecated List
Page Appendix A: Attribute Conventions
Deprecated attribute, originally designed to indicate whether byte values should be treated as signed or unsigned. The attributes valid_min and valid_max may be used for this purpose. For example, if you intend that a byte variable store only non-negative values, you can use valid_min = 0 and valid_max = 255. This attribute is ignored by the netCDF library.
Page File Structure and Performance

The _netcdf_dim_info dataset (in group _netCDF) contains the ids of the shared dimensions, and their length (0 for unlimited dimensions).

The _netcdf_var_info dataset (in group _netCDF) holds an array of compound types which contain the variable ID, and the associated dimension ids.