turns <TT
CLASS="SYMBOL"
>NULL</TT
> if memory could not be allocated. It is
      exported because some applications find it useful to generate result
      objects (particularly objects with error status) themselves.  If
      <TT
CLASS="PARAMETER"
>conn</TT
> is not null and <TT
CLASS="PARAMETER"
>status</TT
>
      indicates an error, the current error message of the specified
      connection is copied into the <TT
CLASS="STRUCTNAME"
>PGresult</TT
>.
      Also, if <TT
CLASS="PARAMETER"
>conn</TT
> is 