dynamic file alocation in COBOL

[MJD1]

How do you do dynamic file allocation in COBOL in an IBM/MVS environment? Changes in JCL setup? Some differences in the select/assign? Differences in open/close?

If you have details or a good reference point, it would be appreciated.

George

 

[slade]

Hi Def,

Try mvshelp.com. Click on their help boards and do a search on "dynamic allocation". Most of the posts may be unavailable, but one or two may give you what you're looking for.

Regards, Jack.

 

[saginaw]

I do not know of a way to do dynamic allocation in COBOL. This is usually accomplished when the file I/O is done in a callable assembler program (mainframe assembler can do this). The dynamic allocation is actually perfomed by an MVS, SVC 99. A DYNALLOC macro is provided in the assembler world to do this specific funtion. Since this is not a mainframe assembler forum I will not digress further. If you want additional information send me an e-mail at helpdesk@simotime.com.

 

[Crox]

Hi,

a TSO command can do this. You can activate TSO by a call in your program.

CALL 'IKJEFT01' USING COMMAND-LINE.

TSO can do this by something like:

ALLOC DA('THIS.IS.YOUR.FILE') FILE(MYDDNAME) SHR

There are several possibilities to call TSO, there are several ways to call it and commands in TSO can also be done from an input file.

Lots of documentation are in IBM's manuals which can be found on-line:

http://www.s390.ibm.com/bookmgr-cgi/bookmgr.exe/FINDBOOK?filter=OSVS+ASCII&SUBMIT=Find

I hope this helps