Offset

An offset variable is a locator used only in conjunction with an area variable. The value of an offset variable specifies the location of a based variable within an area, relative to the beginning of the area.

Offset variables can be assigned, compared for equality and inequality, passed as arguments, and returned as function results. No calculations or conversions can be performed on them, except in the context of explicit conversion to a Pointer, using Open PL/I's POINTER built-in function.