Re: New Opcodes - %SETCELL

[dhandy@xxxxxxxxxxx (Douglas Handy)]

Scott,

>Not only does it seem more "modern" to use service programs instead
>of SPECIAL files, but...  and forgive me if I'm wrong...  don't
>SPECIAL files require "record-based" I/O?
>
>I mean, you use set-length parameters to call your special program,
>don't you?
>
>Seems to me that this largely defeats the purpose of using a
>file in the IFS in the first place.

Typically a SPECIAL file would use record based I/O.  But that doesn't
mean they have to be fixed length records, although you would need to
code a record length to use as a maximum data length to be returned.

There is an implicit parameter list passed to the SPECIAL handler
program, but this can be overridden and you can pass additional
parameters beyond the requisite first four.  In the case of IFS, you'd
likely want to add parms to specify the path and file to be used,
sharing/lock levels, fixed width vs variable length records and record
delimiter, whether you wanted ASCII translation, etc.

But in the end you still haven't gained anything over just using
service program routines, except for not needing a /COPY for the
prototypes and naming the binding directory.  And you could use
READ/WRITE or whatever, if you considered that more readable than
calls like ReadIIFS().

Oh yeah, and you could use I specs to set your record identifying
indicators on input, and O specs for formatting your output. <g>

I'd prefer the service program method myself.  

Doug
+---
| This is the RPG/400 Mailing List!
| To submit a new message, send your mail to RPG400-L@midrange.com.
| To subscribe to this list send email to RPG400-L-SUB@midrange.com.
| To unsubscribe from this list send email to RPG400-L-UNSUB@midrange.com.
| Questions should be directed to the list owner/operator: david@midrange.com
+---