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sanat · Posted: Thu May 15, 2003 8:33 am Post subject: Static Calls

When I look at the manuals regaring Dynamic calls, I get lot of advantages of using Dynamic calls. Can someone tell me what are the sadvantages of using Static calls? Which situation specifically requires that link-editing to be done statically? (It was an interview ques)

One more ques, Why DYNAM option is not allowed in CICS-COBOL compilation?

kolusu · Posted: Thu May 15, 2003 8:07 pm Post subject:

Sanat,

Some of the advantages of static calls are:

Fewer files are needed to distribute your application because your application can be built into a single EXE file, or perhaps an EXE for your main, and a couple of DLLs for subordinate modules. This generally makes it simpler to distribute and/or upgrade your end users.
No risk of mixing/matching different versions of your called subroutines, because they are bundled into your main program.
Dynamic calls takes longer to load, since it has to search the executable libraries for each subroutine.

DYNAM/NODYNAM is a compiler option that determines when a program's subroutines are link edited.

The DYNAM compiler option must not be used by programs that are translated by the CICS translator.

Check the following links for differences between static and dynamic calls

http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/IGY3PG00/4.1.3.3?DT=20011203125201

[url=http://www.naspa.com/PDF/2000/0600%20TS%20PDFs/T0006010.pdf]Static VS Dynamic Linkage in cobol

Check this link for various ways of calling a subroutine in CICS

http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/BOOKS/dfhlp314/1.2.1.7

Hope this helps...

cheers

kolusu

Himesh · Posted: Tue May 20, 2003 2:23 pm Post subject:

A good article discussing the same topic in the NASPA site (and i must add that the topic has been very well explained by Mr. Jim Moore).

Static vs. Dynamic Linkage in COBOL

regards,
Himesh

blitz2 · Beginner Joined: 23 Jan 2007 Posts: 84 Topics: 14

NASPA link does not work
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EXPERT INSURANCE

CICS Guy · Intermediate Joined: 30 Apr 2007 Posts: 292 Topics: 3

Well, it has been a loooong time......

dbzTHEdinosauer · Posted: Fri Jul 13, 2007 3:56 am Post subject:

In addition to those mentioned earlier:

Advantage of Static CALLs: Can use Entry-Points, which can speed-up the processing flow (i.e. Don't have a decision Matrix to execute)

Disadvantage of Static CALLs: If a sub-routine changes and is called in many run-units, all the run-units need to be re-linked. (e.g. Primary master I/O module with Entry-Points - what ever run-units access a master file need to be relinked.)

Advantage of Dynamic CALLs:

Change a sub-module
- no need to relink CALLing module(s)
- smaller package update for customer - can be online update
If you know that a sub-module will only be CALLed once, you can CANCEL it, thus you can manage your memory resources.

Disadvantage of Dynamic CALLs: Can NOT use Entry-Points

The load process for dynamic is slower for the first CALL, because it needs to be loaded, but after the first CALL, the submodule is in memory until CANCELed. So, subsequent CALLs to non-CANCELed sub-routines are not any slower than those with static-linking.

edited by dbz to add a static advantages and dynamic disadvantage - knew there had to be some, just could not think of any.
_________________
Dick Brenholtz
American living in Varel, Germany

dbzTHEdinosauer · Posted: Sat Jul 14, 2007 1:22 am Post subject:

Blitz2,

This is an active link to Jim Moore's article
_________________
Dick Brenholtz
American living in Varel, Germany