It is possible to attach an integer Pick Identifier to primitives which are stored in segments using the routine:
CALL GSPKID(PCID)This inserts one or more Pick Identifiers (PCIDs) into a segment, and these are associated with the subsequent primitives. If one of these primitives is picked sometime later using a Logical Pick input device (see on Page
), then one of the
pieces of information returned to the application is its PCID.
As the application is free to choose the value of the Pick Identifier, this provides a second level of naming, and provides a mechanism to refer back to an application database. For example, if the identifiers 1 to 4 were attached to the four wheels of a car, then picking wheel number three would return the identifier '3' to the application program.