How and when to use keyword "SECTION"?

ankit.jain · New User Joined: 02 Jul 2009 Posts: 18 Location: Mumbai

Hi,

In my code, I observed weird program flow when I added the keyword “SECTION” to a paragraph. Consider the following code as an example:

100-PROCESS SECTION.
<steps>
GO TO 100-EXIT.
100-ERROR.
<steps>
100-EXIT.
EXIT.

200-PROCESS SECTION.
<steps>
200-EXIT.
EXIT.

300-PROCESS SECTION.
<steps>
300-EXIT.
EXIT.

In this code, the keyword “SECTION” is not used in 100-ERROR. In this case, when the control reaches GO TO 100-EXIT, it executes the 100-EXIT and returns to the next line from where 100-PROCESS section was called.

But when I added the keyword “SECTION” after 100-ERROR (so it will appear as 100-ERROR SECTION), the flow of the program changed. In this case, when the control reaches GO TO 100-EXIT, it executes the 100-EXIT, but after that it executes 200-PROCESS section, then 300-PROCESS section and so on.

Is this correct and why does it happen?

Thanks in advance,
Ankit Jain

Binop B · Posted: Thu Jul 02, 2009 12:27 pm

Hi Ankit,

Its been sometime since i have come across SECTION concept. I will tell what i remember.

SECTIONs can be considered to logical parititions within a DIVISION. In your case here SECTION is supposed to be logical divisions to your PROCEDURE division.

Now I hope u know the general difference between GOTO and PERFORM. The general idea is when we do a PERFORM statement to call a paragraph it executes the same and control returns back. When we do a GOTO para it executes the same para but continues the execution with the next paragraph in line.

When a PERFORM to a section is done ( in this case 100-PROCESS ), if i remember correctly, the whole SECTION is executed. In the example given above, you have basically given a GOTO within the SECTION. As far as the initial PERFORM is concerned the control is still within the SECTION hence after executing 100-EXIT it returns back to the statment after the PERFORM 100-PROCESS statement. Please note that if there were other paragraphs after 100-EXIT ( before the next SECTION ) it would execute those paragraphs also and then only return back to the initial PERFORM statment.

In the second case you have mentioned when you are doing a GOTO to a completely new SECTION, the initial PERFORM looses its flow as it has come out of the expected flow and hence the initial PERFORM is terminated. Hence after executing the 100-EXIT SECTION it continues on with the next paragraph.

Hope i have been of help.

ankit.jain · New User Joined: 02 Jul 2009 Posts: 18 Location: Mumbai

Thanks a lot Binop, your explanation is really helpful and I appreciate the way you explained it.

Binop B · Posted: Thu Jul 02, 2009 1:57 pm

Nice to hear that...

Bill O'Boyle · Posted: Thu Jul 02, 2009 4:45 pm

Procedure Division "SECTIONS" have been steadily falling out of favor, except when they are mandated, such as COBOL INPUT and OUTPUT SORT PROCEDURE SECTIONS. However, USING and GIVING t/w the FASTSRT compile option instead, seems to be more of the rule.

When compiling a program which uses SECTIONS and specifying the OPT compiler option, you'll find that the generated Load Module tends to be slightly larger than a program without SECTIONS, excluding the SORT PROCEDURE SECTIONS as outlined above.

FWIW, INPUT and OUTPUT SORT PROCEDURE SECTIONS are akin to E15 and E35 Sort Exits, respectively.

Regards,

dick scherrer · Posted: Thu Jul 02, 2009 8:22 pm

Hello,

Bill O'Boyle · Posted: Thu Jul 02, 2009 8:32 pm

Thanks Dick. I had thought just the opposite in regards to performance as IBM touts USING/GIVING as a faster way to perform sorts in COBOL.

Yes and that's a true statement that FASTSRT has no effect on INPUT and OUTPUT Procedures.

Heaven forbid, but do you think they've not been entirely forthcoming regarding USING/GIVING?

Never would have thunk it....

Regards,

Robert Sample · Posted: Thu Jul 02, 2009 8:49 pm

IBM touting something that increases the need for hardware? Who woulda thunk it?