This opens the FITS file associated with the specified parameter, and adds headers to the primary FITS header that record the number and names of all the immediate parents in the supplied NDG provenance structure. It then closes the FITS file. It also records the number of root parents—those without ancestors—and their observation identifiers from component OBIDSS within the MORE component of the supplied provenance structure. These are the observations.

The names follow CADC convention as follows. For the immediate parents:

PRVCNT = _INTEGER / Number of parents PRV1 = _CHAR / Name of the first parent PRV2 = _CHAR / Name of the second parent : : : : : : PRVn = _CHAR / Name of the PRVCNTth parent

for the root provenance: OBSCNT = _INTEGER / Number of root-ancestor headers OBS1 = _CHAR / First observation identifier : : : : : : OBSn = _CHAR / OBSCNTth observation identifier

and the output file name: FILEID = _CHAR / Filename without extension

The above headers are prefaced by a blank header and a title " Provenance:" comment.

The PRODUCT keyword’ s value is modified for FITS extensions. It has ’ _$<$extname$>$’ appended where $<$extname$>$ is the lowercase name of the standard EXTNAME keyword.

CALL CVG_SCADC( IPROV, PARAM, STATUS )

IPROV = INTEGER (Given)

PARAM = CHARACTER $\ast$ ( $\ast$ ) (Given)

STATUS = INTEGER (Given and Returned)

• Ancestors that have been flagged as " hidden" are ignored.

• A warning is issued if the OBSIDSS component cannot be found for a root ancestor. The value of OBSCNT gives the number of ancestors with an OBSIDSS value.