On entry to an OPS/REXX program, the field EFPLEVAL in the external function parameter list (the EFPL whose address is passed in register 1) points to an EVALBLOCK, an evaluation control block. The evaluation control block is an area the caller preallocated to return a function result. A routine need not return a result if a REXX CALL instruction invoked it; but a function result must be returned in all other cases.
Copy the result (a string) into the EVALBLOCK_EVDATA. Check the maximum length of this field to make sure that you do not overlay storage. The EVALBLOCK that CA OPS/MVS builds can contain a 32,000-byte result value.
The length of the returned string should be stored as a fullword integer in field EVALBLOCK_EVLEN. On entry to a routine, the caller has primed this field with the value X'80'. If this value returns unchanged, the function returns no result.
|
Copyright © 2014 CA.
All rights reserved.
|
|