I'm not talking about how the Cobol standard has them specified. Just
that,
as a feature, I would like some better way to work with variable length
strings.
With regard to DIRECT... Without actually reading the standard, here is
what I would intuitively *expected* with regard to a direct "any length"
data item (fixed length font required for this to make any sense at all!):
01 AN-01-DATA-AREA.
05 FIXED-STR-10 PIC X(10).
05 VARIABLE-STR-10 PIC X ANY LENGTH LIMIT IS 10 DELIMITED BY
X'00'.
05 A-CHAR PIC X.
MOVE 'XXXXXXXXXX' TO FIXED-STR-10
MOVE 'TEST' TO VARIABLE-STR-10
MOVE 'Z' TO A-CHAR
MOVE 'YYYYYYYYYY' TO VARIABLE-STR-10
Result in memory, before the final MOVE:
XXXXXXXXXXTEST_ Z
^^^^^^^^^^^^^^^^^^^^^^
After the final MOVE:
XXXXXXXXXXYYYYYYYYYY_Z
^^^^^^^^^^^^^^^^^^^^^^
The underscore represents the delimiter 'null' character.
What you say says to me that before the final move we would instead see
XXXXXXXXXXTEST_Z
I would agree that this is rather crazy.
I think how I am looking at it, which is apparently not how you would
sup****t it, is that if DIRECT is specified *along with a limit*, then the
maximum storage required would be used. This is just like how in C you
can
have, for instance:
struct my_struct {
char[21] field1;
char[21] field2;
char x;
};
void cfunc(struct my_struct *s) {
strcpy(s->field1, "This is a test");
strcpy(s->field2, "Another test");
s->x = 'X';
}
Result in memory:
This is a test_ Another test_ X
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
If I wanted to call cfunc from Cobol I could do this:
01 MY-STRUCT.
05 field-1 PIC X ANY LENGTH LIMIT IS 20 DELIMITED BY X'00'.
05 field-2 PIC X ANY LENGTH LIMIT IS 20 DELIMITED BY X'00'.
05 X PIC X.
CALL 'cfunc' USING MY-STRUCT
DISPLAY field-1 '/' field-2 '/' x
Result:
This is a test/Another test/X
Now as for a DIRECT any-length data item without a limit specified, I
don't
think that makes sense. Is it even allowed? My brain doesn't want to try
to interpret the standard right now.
Frank
n 4/1/2008 at 8:54 PM, in message
<vzCIj.8760$fY6.7941@[EMAIL PROTECTED]
>, William M.
Klein<wmklein@[EMAIL PROTECTED]
> wrote:
> Frank,
> As currently included in WD 1.10, I am very much opposed to it. The
> problem
> is that the current definition allows the data to be stored within the
> structure
> ("DIRECT") and to have such items within ODO's and with data after this.
> What
> this means is that the "data" after the variable length field MUST be
> "moved" in
> storage each time the variable data size changes.
>
> If the proposed definition
> - only allowed for "direct" variable length fields at the 01-level,
> - allowed for "indirect" variable length items within structures
> - figured out how to handle such fields within FILES (or disallowed it
> there),
> - didn't allow the same variable length field to be BOTH prefixed and
> suffixed
>
> then I would be for it.
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