Re: Knotty puzzle with chaining to files not known at compile time

["James H H Lampert" <jamesl@xxxxxxxxxxx>]

Frank Kolmann wrote:
> . . . Just a small point, one Fspec will do. Just use a Key 
> length of 99 or so. . . .

My first (and as it turned out, only) experiment was based 
on Mr. Kolmann's suggestion (because it seemed more 
idiomatic to RPG, and therefore easier to maintain), and 
was implemented as follows (only the filenames, were 
changed to protect the innocent; some spacing was 
condensed to avoid unwanted line breaks):

FFOO       IF   F   43    18AIDISK
FBAR       IF   F   43    18AIDISK
FBAZ       IF   F   43    18AIDISK
D REC             DS
D CONTENT                 1     43
C                 CLEAR              KEY              18
C                 SETOFF 
                                13
C                 EVAL     KEY = '00010012900001'
C   KEY           CHAIN    FOO       REC 
                13
C 13'FOO FAILED!' DSPLY
C   CONTENT       DSPLY
C                 SETOFF 
                                13
C                 EVAL     KEY = '010000001015300001'
C   KEY           CHAIN    BAR       REC 
                13
C 13'BAR FAILED!' DSPLY
C   CONTENT       DSPLY
C                 SETOFF 
                                13
C                 EVAL     KEY = '1000000005800001'
C   KEY           CHAIN    BAZ       REC 
                13
C 13'BAZ FAILED!' DSPLY
C   CONTENT       DSPLY
C                 SETON 
                                 LR

The key length was set to the maximum possible key length; 
the record length was set to the minimum possible record 
length; the key was specified as a string literal. In no 
case did a "FAILED" message appear (I used known-good keys 
for the test); in all 3 cases, the correct first 43 bytes 
of the record were quite recognizable.

Thanks for ALL of the suggestions; hopefully this thread 
was educational for a lot of us. It certainly was for me.

--
JHHL