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rgk · Beginner Joined: 11 Feb 2003 Posts: 6 Topics: 3

I have a doubt in Occurs Depending On Clause
When i have two ODOs within a group level variable i need to give the count variable for both the ODOs before the ODO clause like in the following code.

Manas Biswal · Posted: Tue Feb 11, 2003 4:36 am Post subject:

Hi Kannan,

The following is an explanation of your problem as far as my knowledge goes. Gurus - Please correct me if I am wrong.

Basically, when you compile a program, the compiler checks your code syntax and then generates offsets for all your working storage variables from a Base Locator(BLW). It does not allocate memory for the WS variables. It just generates offsets for all the variables with respect to a base. After compilation, the object code contains everything(all your reference to the WS variables in MOVES,COMPUTES etc. ) in the form of those offsets. Now, during run of the program, the base address is determined depending on where contigouous memory area is available for all the variables. After the base address is determined, memory is allocated for all the variables depending on the pre-determined offsets. This is clear for static WS variables.
Now, let us consider dynamic variables where DEPENDING ON clause is used. Now, if you use a DEPENDING ON clause, then offsets cannot be generated at compile time for the OCCURS variable because the exact number of times the variable will occur will be known only at run time. In such a case, if you put another variable below the variable which OCCURS DEPENDING ON, then offset of the other variable also cannot be obviously determined at compile time. Thats why you could not put WS-COUNT2 below WS-ODO1.
However, if you put WS-COUNT2 in a separate group level variable, offset will be generated for it as each 01 level variable starts from a separate boundary.

Hope all this makes sense. Smile

Regards,
Manas

rgk · Beginner Joined: 11 Feb 2003 Posts: 6 Topics: 3

Hi Manas,
Thanks for your reply. Can you tell me where could i get information about this BLW and the funda behind it?
Thanks in Advance,
Kannan

somuk · Beginner Joined: 04 Feb 2003 Posts: 113 Topics: 37

Hi Kannan,
Try this..

Manas Biswal · Posted: Wed Feb 12, 2003 6:08 am Post subject:

Hi Kannan,

Basically, the way I knew about this was, after seeing all the BLW and offset listings on the compilation listing, I asked someone about it and he told me about the meaning of BLWs and offsets. I have never done an extensive study on these topics because I practically don't need these concepts often. I will try to get you some links. If somebody here provides me with some link, then i will also benefit from it.

Regards,
Manas

rgk · Beginner Joined: 11 Feb 2003 Posts: 6 Topics: 3

Thanks Manas

Regards,
Kannan

Novice · Beginner Joined: 27 Dec 2002 Posts: 46 Topics: 15

Manas, Just had the same doubt which Kannan had and your explanation addressed it. Can you suggest some further reading in BLW/BLL's?

Regards
'Novice

dtf · Posted: Thu Mar 31, 2005 1:31 pm Post subject: