The XMM-Newton calibration data base is a collection of algorithms ( described in the Calibration Handbook ), and Current Calibration File (CCF) constituents . The latter contain the numerical values driving the calibration algorithms.
The SAS tasks access the calibration data base through the Calibration Access Layer (CAL, cal). The CAL is pointed to the correct set of CCF constituents through a CCF Index File (CIF).
cifbuild is used to generate the CIF appropriate to a given observation and analysis date.
Details on how to use a CIF in conjunction with the SAS, and what environment variables must be used, can be found in the CAL documentation.