Find position of primitive in HDS file DAT_WHERE
The use of this routine is not recommended. It is provided solely for use by experienced programmers who are familiar with the internal structure of HDS container files and who wish to access the file contents directly. Note, however, that changes to the format of an HDS file may occur in future.
The start of the data associated with a cell or a slice of a primitive object may be located with this routine, but the data associated with a slice will not, in general, be stored at contiguous locations within the file.
Care must be taken that no changes are made to adjacent bytes within the file which are not part of the requested object’s data.
Note that the data associated with primitive objects may not necessarily be stored contiguously in future versions of HDS.