Hadley Willan <hadley.willan@deeper.co.nz> writes:
> Okay, me again. I was readin the psql source and noticed that (df)
> describeFunction explicitly excludes return type 0 which just happens to
> be opaque. I did a select on pg_proc and the functions that had the
> return type 0 happened to be returns OPAQUE.
> Does anybody know why this would be the case?
I believe the original idea was to avoid cluttering the display with
datatype I/O functions. In 7.3 we've narrowed the scope of this check
so that only functions taking/returning type "cstring" are suppressed.
regards, tom lane