Release 3.5beta5 is mostly bug fixes and portability enhancements to version 3.4, but also includes Robert Pincus's Fortran90 interface. The netCDF file format is still unchanged, so files written with previous versions can be read or written with version 3.5.
There is a change in behavior: In netCDF 3.4, calling nc_close() or nc_endef() would remove any extra space in the header, causing all the data values to be moved up (towards the beginning of the file) if the space needed for the file header had decreased due to deleting an attribute or decreasing the number of attribute values. This was not the intended behavior and could be very costly for large datasets. In this version, extra space in the header persists and the size of the header will never shrink as the result of netCDF function calls. Hence space "reserved" by calling the nc__endef() function will be preserved for later efficient additions of new attributes or non-record variables.
nc__create_mp() nc__open_mp() nc_set_base_pe() nc_inq_base_pe()