IBM OS/390 User Manual

For example:

01

RECORD-A

PIC X(4).

01

FILLER REDEFINES RECORD-A.
10

RECA-FIRST

PIC 9(2).

10

RECA-SECND

PIC 9(2).

Using COBOL for OS/390 and VM you will receive the message:

IGYDS1064-E A 

″

REDEFINES

″ 

clause was found in the definition of a

level-01 item in the 

″

FILE SECTION

″. 

The clause was discarded.

This coding practice is documented as invalid in DOS/VS COBOL, but
DOS/VS COBOL did not flag the error.

•

With DOS/VS COBOL you can specify the 

SELECT OPTIONAL

 clause, for an input

file that is to be accessed sequentially, and that may not be present each
time the program is executed. However, if you do specify

OPTIONAL

, it is

treated as a comment, since for DOS/VS COBOL this function is performed
by the 

ASSGN

 job control statement with the 

IGN

 parameter.

In COBOL for OS/390 and VM 

SELECT OPTIONAL

 is required for a file that may

not be present each time the program is executed, and which is opened in
input, I/O or extend mode.

Therefore, if you have made use of the 

OPTIONAL

 key word only as a

comment, you should remove it, as your program may produce unpredictable
results.

•

DOS/VS COBOL will accept the 

ACCEPT

identifier

FROM SYSIPT

 statement

without the keyword 

FROM

. COBOL for OS/390 and VM does not. It will

generate the message:

IGYPS2072-S 

″

SYSIPT

″ 

was invalid. Skipped to the next verb, period or

procedure-name definition.

•

The program name supplied in the 

PROGRAM-ID

 paragraph is a user-defined

word that identifies the program. If this name contains a 

′

−

′

 COBOL for

OS/390 and VM will converted it to 0. This was true of DOS/VS COBOL also,
but COBOL for OS/390 and VM generates a warning message,

IGYDS0020-W

,

for example,

IGYDS0020-W

Name 

″

C2NAC-30

″ 

was processed as 

″

C2NAC030

″ .

•

On returning to a COBOL calling program from an Assembler or other
language subroutine, data is left in register 15. In DOS/VS COBOL it did not
matter what this data was. In COBOL for OS/390 and VM the value in register
15 is passed to the 

RETURN-CODE

 special register. At the end of the program

the value in the 

RETURN-CODE

 special register is returned to OS/390 as a user

return code. If there was invalid data in register 15 on the return to the
calling program, (and therefore also in the 

RETURN-CODE

 special register), the

application may produce an unexpected return code from OS/390, or even a
dump.

This problem may be circumvented by adding the following statement to your
converted source code:

MOVE 0 TO RETURN-CODE

RETURN-CODE

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