No leap second change in this version. The last time the leap second table
was modified to add a new second on 01-01-2017.
For all data producers, including IDL, MATLAB, etc, users, you should upgrade
to the latest release based on CDF V18.104.22.168.
For those users that only read the CDF files, you are strongly
encouraged to upgrade the software/patch version now. If you want
to delay upgrading the software/patch version at this moment,
this is the new
Leap Second Table that should be used. Make
sure that one of the following environment variables is set:
CDF_LEAPSECONDSTABLE (for non-VMS system), or
CDF$LEAPSECONDSTABLE (for VMS systems)
It should point to the new leap second table.
If the CDF file was made with older CDF version and leap second table, it
might be rejected by the CDF's sanity check if its data has any TT2000 time
later than 1/1/2017. To read the file, you need to have to set another
CDF_VALIDATE (for non-VMS system) or
CDF$VALIDATE (for VMS systems)
In the distributed source or pre-built package, there is a command-line based
tool program that can be used to check where the leap second table is and
how it is being used. IDL and MATLAB also has a similar module.
For Linux/Unix/MacOSX/Windows: use the command line tool:
it will show whether an external table or a hard-coded table in
the library is used, and when the last leap second is added.
For IDL, use cdf_leapseconds_info module to get the
leap second table information.
The tags: USE_FILE, CDF_LEAPSECONDSTABLE and LASTUPDATED from the
info structurfe will have the relevant information.
For MATLAB, use spdfcdfleapsecondsinfo module to get the
leap second table information. Run:
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