Keyword POS not allowed when start position implied by a special keyword.
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Cause . . . . . : The POS keyword is not allowed when one of the special keywords is used to define both the data type and the start position.
Recovery . . . : Remove the POS keyword. Compile again.
Technical description . . . . . . . . : The special keywords are *FILE, *INP, *MODE, *OPCODE, *OUT, *PARMS, *PROC, *RECORD, *ROUTINE, *SIZE, and *STATUS.