RE: QDFRTVFD on V7R1

Excellent response Chuck.

Here was the result after the first call:

QDFRTVFD(DSPF0100 :8 :'DSPF0100' :FILE :APIERRORDS);

DSPF0100.BYTESRETN = 8
DSPF0100.BYTESAVAIL = 27688

First 16 bytes in hex:
00000008 00006C28 40404040 40404040

Note the last 8 bytes are blanks.
The APIERRORDS returns no error. (i.e. APIERRORDS.BYTESAVAIL = 0)

Second call:

QDFRTVFD(DSPF0100 :DSPF0100.BytesAvail :'DSPF0100' :FILE :APIERRORDS);


DSPF0100.BYTESRETN = 27688
DSPF0100.BYTESAVAIL = 27688

First 16 bytes in hex:
00006C28 00006C28 40404040 40404040

The last 8 bytes are still blanks.

The size of the user space before and after the call was 16384 bytes.

To test if the size was an issue I ran this code to trigger the user
space to extend.
ptrExtend = ptrDSPF0100 + DSPF0100.BytesAvail+1;
ExtendChar =' ';

This sets a blank to the location after what is needed by the API.

The required size of my user space to contain the 27688 bytes should be
around 35461.
After the extend code ran the user space size was 49152. More than
enough.

To test, I ran this code to retrieve the data.
QDFRTVFD(DSPF0100 :DSPF0100.BytesAvail :'DSPF0100' :FILE :APIERRORDS);

Again, the API states that the data was returned however no was actually
loaded.

DSPF0100.BYTESRETN = 27688
DSPF0100.BYTESAVAIL = 27688

First 16 bytes in hex:
00006C28 00006C28 40404040 40404040

Next I tested your suggestion for the second parm to require a copy.
QDFRTVFD(DSPF0100 :DSPF0100.BytesAvail*1 :'DSPF0100' :FILE
:APIERRORDS);

In this test the data is loaded into the user space.

First 16 bytes in hex:
00006C28 00006C28 0018000F 00000100

I then removed the code to force the extension of the user space and
tested again using the "*1" parm.
Again, the user space was auto-extended and the data was returned.

If find it strange that the location of the input variable would matter
to the QDFRTVFD API for a parameter that the API defines as input. I
think I'll have a PMR opened with IBM to make sure this is the intended
operation of the API.


Chris Hiebert
Programmer/Analyst
Disclaimer: Any views or opinions presented are solely those of the
author and do not necessarily represent those of the company.