Re: Fw: Are level checks still useful?

[Mark S Waterbury <mark.s.waterbury@xxxxxxxxxxxxx>]

Hi, Chuck:

Thanks for that clarification / correction.

Mark

> On 11/2/2012 9:46 AM, CRPence wrote:
> On 01 Nov 2012 17:57, Mark S Waterbury wrote:
> > When the program is compiled over a file with LVLCHK(*YES) specified,
> >   the program incorporates a copy of the Record Format Level ID for
> > each record format in the file. Then, when the file is opened, a
> > setting in the UFCB (User File Control Block) controls whether the
> > data management open routine checks to verify that the record format
> > level IDs in the program match those in the current file to be
> > opened... if not, the data management open routine sends CPF4131 as
> > an *ESCAPE message to the caller (your program), generating an
> > exception.  If you issue OVRDBF ... LVLCHK(*NO) prior to opening the
> > file, or the program was compiled for a file with LVLCHK(*NO)
> > specified, then this check is not performed, so you will not get this
> > exception issued by the data management open routine.
>     Per my understanding and in my experience, I am confident of one
> correction to the above...
>
>     The compiler copies and stores the Record Format Level Identifier for
> later run-time comparison, and that information is shown in DSPPGMREF,
> irrespective of the LvlChk setting that was established for the file
> during compile-time.  The stored value will always be compared for Level
> Check validation at run-time whenever the file is LVLCHK(*YES) and no
> override exists for LVLCHK(*NO).  This is the case even if the program
> had originally been compiled either against the file with LVLCHK(*NO) or
> an override to LVLCHK(*NO) for that file; e.g. if the file was
> originally defined with LVLCHK(*NO), the program compiled with no
> overrides in effect, then CHGPF LVLCHK(*YES) was effected, and finally
> the program called, that run will perform the Data Management level
> checking.