HDSPAR is a library of subroutines which interface between the Starlink Hierarchical Data System (HDS) and the ADAM parameter system.
The subroutines do things like opening, closing, creating and deleting HDS objects (see SUN/92) but instead of passing the object name to the subroutine, the name of a program parameter is passed. The parameter system then associates the parameter with the required object, using the normal parameter system process, involving the Interface Module (see SUN/115) and possibly prompting the user.
Apart from DAT_CANCL, all the routines obey the Starlink error-handling convention described in
SUN/104 – if the STATUS argument is not SAI__OK on entry, they return without action; if they detect
an error, they report an error message and return an appropriate STATUS value. DAT_CANCL will attempt
to operate regardless of the given status value.