which record will be read in called program

jyothimenon1 · New User Joined: 16 Jul 2008 Posts: 9 Location: bangalore

here what will happen?

I have a doubt regarding open a file in one program and use it in its called program

Consider the scenario where I read 10 records from the file using the main program and if I gave a read in the called program then will I get the 11th record or the first record? (Here Im talking about the case that we are not carrying any key info from the main program to the sub program)

dbzTHEdinosauer · Posted: Wed Jul 30, 2008 12:34 pm

batch or online.

if batch, you need two fd's, which means what you read in the second has nothing to do with the first.

if online, and you are passing keys, and you can only read vsam, you are going to have diddely in the second.

sudhakar84 · New User Joined: 20 Jun 2008 Posts: 25 Location: chennai

dbzTHEdinosauer , Thanks for the info.

jyothimenon1 · New User Joined: 16 Jul 2008 Posts: 9 Location: bangalore

hai dbzTHEdinosauer,

Thank you so much for the reply

Robert Sample · Posted: Wed Jul 30, 2008 5:09 pm

Is it a COBOL EXTERNAL file? Does the subprogram have a separate file definition and open? The answer will vary depending on the precise environment ....

jyothimenon1 · New User Joined: 16 Jul 2008 Posts: 9 Location: bangalore

hai Robert

The sub program have seperate FD then what will happen?

please help me if there is no seperate FD for sub program, is it possible ?

In the case of external file declared in calling program , is there need to declare FD again in called program?

Robert Sample · Posted: Wed Jul 30, 2008 6:40 pm

I know about EXTERNAL files but haven't used one (so far). The Programming Guide has a write up with examples:http://publibz.boulder.ibm.com/cgi-bin/bookmgr_OS390/handheld/Connected/BOOKS/IGY3PG20/4.2.6.1?DT=20040220035836 of how to do the main and subprogram(s).

Douglas Wilder · Posted: Wed Jul 30, 2008 7:47 pm

If the file is declared external, both programs will have an FD with "external" in it. In this case if one program reads 10 records, then the next record read by either program will be the 11th record.
If the file is not external, both programs will have an FD, but each program must open the file and they are independent. If one program reads 10 records and then the other program reads a record, it will get record 1.