Dean Asmussen (DAsmussen@aol.com) wrote:

>>  If you're going to use LVLCHK(*NO) to avoid recompiling programs that
>>  reference the file for input, then you have no choice but to put the new
>>  fields at the end. The programs will be using the record definition as
>>  it was at before the layout changed. If you put the fields at the end
>>  they simply won't see the new fields. Put them anywhere else and all
>>  hell will break loose.
>
>Ahhh, but I DISAGREE with level check *NO.

So do I, although not quite as vehemently as you. I wasn't recommending
it, just clarifying the point.

>>  Actually I'm all in favour of it. It doesn't do anything you couldn't do
>>  before, and it doesn't work instantaneously. It's not "on the fly" in
>>  that sense. It just makes a complex process simpler and less error
>>  prone. I can't see that's such a bad thing.
>
>How so?  I'd appreciate the "particulars"...

The process of moving the old physical file, moving the old logicals,
creating the new physical, copying the data, creating the new logicals,
deleting the old logicals, and deleting the old physical (that's how I
do it, anyway) is complex and I know it's one that's caused problems for
people in the past. OK, I have the process automated, but the routine is
a tricky one to write. CHGPF does it all for you in one command.

I don't think the point of the new abilities of CHGPF is to encourage
people to use LVLCHK(*NO). It's just an option that was always there on
CRTPF and CHGPF. I occasionally use LVLCHK(*NO), but I only use it to
speed things up when I'm programming and the effects of what I'm doing
is strictly localised.

BTW people who insist on using LVLCHK(*NO) with the CHGPF command should
take care. It only applies to the physical. The level checking of any
dependent logicals remains the same. You will need to track down any
dependent logicals whose format level ID will have changed and set them
to LVLCHK(*NO) using the CHGLF command.

Dave Kahn - TCO, Tengiz, Kazakstan
=========

e-mail:  kahn@tengizchevroil.com    (until September 30th)
         dkahn@cix.compulink.co.uk  (from  October 1st)
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