OGR WRAP character

Frank Warmerdam fwarmerdam at GMAIL.COM
Fri Jul 8 11:11:51 EDT 2005

On 7/8/05, Daniel Morissette <dmorissette at dmsolutions.ca> wrote:
> Frank Warmerdam wrote:
> >
> > My first thought is that the MITAB driver should not be turning char-10
> > into escaped \n format.  The \n character is legal (though possibly
> > occationally a nuicance) in attribute values and I don't think most other
> > drivers fool with special characters like this.
> >
> So should I take this as a clear statement that it is okay (and actually
> the recommended way) for an OGR driver to return strings with
> non-printable characters in them? I guess that was my main question
> before making a decision on what to do about the specific problem
> between MITAB and MapServer.


If the source has unprintable characters, then it is OK to return them
in OGR attribute values.  Stricter rules might apply to things like
attribute names. 
> > Since Daniel "owns" MITAB you guys are welcome go ahead to a
> > change to the behavior if you are comfortable with it, though it might
> > be nice to raise the issue on the mitab mailing list.
> >
> Still not sure what to propose for MITAB: MIF files contain '\' + 'n',
> so that's what users of the lib are likely to expect. If MIF files
> return one thing and TAB files return a different thing then that means
> applications using MITAB need to handle both cases in a different way
> which is ugly. Changing the behavior to return ASCII-10 even in the MIF
> case may be the way to go, I'll have to dig and try to figure out why I
> bothered implementing this escaping in the first place.  yuck!

Ah.  I had missed that mid/mif and tab were different in this regard.
I think it would wise to treat the \n encoding in mid/mif as a format
specific escaping convention and transform into char-10 within OGR. 

Best regards,
I set the clouds in motion - turn up   | Frank Warmerdam, warmerdam at pobox.com
light and sound - activate the windows | http://pobox.com/~warmerdam
and watch the world go round - Rush    | Geospatial Programmer for Rent

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