calculate position and offset

anirudh1985 · New User Joined: 22 Aug 2007 Posts: 66 Location: bangalore

hi, i have a copybook declaration as follows:

id pic x(5)
name pic x(10)
city pic x(10)

how do i calculate the position and offset of the values id,name,city .My out put shud be:
field pos off
id 1 5
name 6 10
city 16 10

can any body help me....

dbzTHEdinosauer · Posted: Wed Jun 11, 2008 11:23 am

depends on if you want cardinal position or relative position.

dick scherrer · Posted: Wed Jun 11, 2008 11:30 am

Hello,

Suggest you change terms to position or displacement and length.

This is most likely a task you do not want to undertake. . .

Your code would need to replicate much of the data division functionality of the cobol compiler and that is usually not reasonable.

Depending on how you want to use this info, you can probably get these values from a compile listing.

anirudh1985 · New User Joined: 22 Aug 2007 Posts: 66 Location: bangalore

for example i need to calulate for pic x(5) as follows

start pos is:1 and offset is :5

now for pic x (10)
start pos is 5(previous offset)+1=6 and offset:10...i hope its clear now

dick scherrer · Posted: Thu Jun 12, 2008 3:43 am

Hello Anirudh,

I believe we understand what you want to do. What is not clear is how the "output values" will be used once calculated.

Pedro · Posted: Thu Jun 12, 2008 6:32 am

1. read your cobol copy file into a rexx stem.

2. starting offset is 1

3. using your basic logic, loop through your stem array parsing the variable name and meanwhile calculating the cumulative offset from start of record.
5(previous offset)+1=6

----
4. read your data records and use names and offsets you figured out earlier. You looked and know the record will be parsed something like this:

dick scherrer · Posted: Thu Jun 12, 2008 6:41 am

Hello,

And don't forget to allow for repeating groups (arrays, even multi-dimensional), redefines (and nested redefines), and the various calculations to determine actual byte length from binary and packed-decimal field definitions. . .

rexx77 · New User Joined: 14 Apr 2008 Posts: 78 Location: Mysore

i feel File aid will help a little bit in this issue. i worked some time back the for a requirement similar to this.

Invoke file aid in Batch mode for the copybook and store the output file in sequential dataset, then take the file for processing using REXX.

File aid will give you in a format like below

Variable datatype length start end

Extract information from the file using simple rexx functions.

Hope this piece of info will help you

Regards

enrico-sorichetti · Posted: Thu Jun 12, 2008 11:56 am

as already asked,
if the TS would graciously tell what he is trying to achieve we might be able to give better answers

is he trying to parse a cobol copybook, looks like, but who knows?
I asked the same in a different thread from the same, but the gentleman did not care to reply
http://www.ibmmainframes.com/viewtopic.php?t=31488&highlight=

here is a pointer to "a cobol copybook length calculation in rexx"

http://groups.google.be/group/bit.listserv.tsorexx/browse_thread/thread/d60c97b35839e3ff/bdcec8b86fb6ecae?lnk=gst&q=rexx+record+calculation#