Null-capable field passed by reference to subprocedure cannot have its null indicator set on

I've just written a subprocedure which receives, by reference, one of a
series of null-capable database fields.  After processing, if the field
contains no data, I want to set its null indicator on, by calling
%nullind() on it, so that when it is written to the database, it will
correctly be identified as null.  However, I get a compilation error,
saying that the field is not null-capable.

Now, since I'm passing by reference, I would expect that the field in
the subprocedure would be null-capable; but it seems not.

I can't find anything about this on the web, in the archives, or in the
redbook.  Is it exhibiting correct behaviour?  I can work around it by
setting the null indicator for the database field in the main body of
the program, but I then have to do that for each field that I pass to
the subprocedure.

For what it's worth, we're at V5R1 and fairly current on PTFs.

Cheers,

Martin.

--
Martin McCallion
Senior Technical Consultant
Work:  martin.mccallion@misys.com
Home: martin.mccallion@ukonline.co.uk
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