NDG_BEGPV - Begin an NDF provenance block

Description:

This routine should be called to mark the start of an NDF provenance block. The block should be ended by a matching call to NDG_ENDPV. See NDG_ENDPV for more details.

Note - provenance blocks must not be nested.

Invocation:

CALL NDG_BEGPV( STATUS )

Arguments:

STATUS = INTEGER (Given and Returned)

The global status.