Re: Fw: Are level checks still useful?

[CRPence <CRPbottle@xxxxxxxxx>]

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.