Re: Dynamic reading of a file

["Jim Franz" <jfranz@xxxxxxxxxxxx>]

You need to define what you mean by "display".
Is this 10 records or 10,000?
If you want to just "see" the data, then use a database utility
like the freeware WRKDBF at www.wrkdbf.com
run the command from your clp or command line, and it will display the
records.
You can add/chg/delete (no edits).
Simpler command is DSPPFM (Display Physical File Member)
hth
jim

----- Original Message -----
From: "Martin Rowe" <martin@dbg400.net>
To: <RPG400-L@midrange.com>
Sent: Monday, May 28, 2001 11:59 AM
Subject: Re: Dynamic reading of a file


> On Monday 28 May 2001 10:02, Madhusudhana Perumal Iyah Guruswamy suresh
> wrote:
> > Hi
> >
> > Can anyone give me some information of reading a file dynamically.
> >
> > The problem is, I know the file to read only at runtime and I have to
> > read the file and display  the data for processing. Is there any way to
> > read a file like this.
> >
> > Any info on this is appreciated.
> >
> > Thanks.
> >
> >
> > Suresh.
>
> Hi Suresh
>
> If your file has the same layout, but a different library or name, then
> you can do a compile against the known file and an OVRDBF to the target
> file at run time, before opening the file. If you don't even know the
> layout in advance then I would use a program described file with a single
> field, big enough to handle the longest record length your runtime file
> is likely to have. Override to the desired file at runtime and use the
> system APIs to get the file layout and field properties, then read in
> each record, substringing each 'field' out of the big field. For
> non-string fields you can map them onto a data structure that has a
> character field overlaying a field of the right type (with maximum size).
> You can then format this data as required for your display (concatenating
> the formatted strings into a single field for subfile display).
>
> I have an example of this technique on my site (see .sig below) where I
> create a comma delimited flat file from a DB2/400 file chosen at runtime.
> In this case all character, packed, zoned, binary, date/time & float[1]
> values get formatted into a character representation so it should be easy
> to load them into a subfile instead. Go to the Extras page (from the main
> page, Extras section) and look for CRTCSVDTA.
>
> Regards, Martin
>
> [1] Not too sure if it's handling these right as I've never come across
> them until writing CRTCSVDTA and setting some up files to test it with.
> If float field are likely to crop up in your database, you may need to do
> some more work ;-)
> --
> martin@dbg400.net / jamaro@firstlinux.net
> http://www.dbg400.net  DBG/400 - DataBase Generation utilities
> Open Source test environment tools for the AS/400 / iSeries and
> miscellaneous database & spooled file management commands.
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