[Dune] Import *.poly file using triangle and the dgfparser

[giese at math.hu-berlin.de]

Dear Dune Developers,

I am stuck in a problem using Triangle and the DGFparser. I have a domain
with holes described in a *.poly file, which I am trying to tessellate
with Triangle and import with the DGFparser.
My DGF-file "A.dgf" reads as follows:

DGF
Simplexgenerator
display 0
path $HOME/Triangle/triangle
file A poly
dimension 2
#
BOUNDARYDOMAIN
default 1
#
# A.dgf

The File "A.poly" is the standard example given in Triangle. It's a domain
with one hole and the shape of the letter "A". (I used this example here
to avoid any other mistakes) Running DUNE I get the following output:

parallel run on 1 process(es)
Opening A.poly.
Constructing Delaunay triangulation by divide-and-conquer method.
Delaunay milliseconds:  0
Recovering segments in Delaunay triangulation.
Segment milliseconds:  0
Removing unwanted triangles.
Hole milliseconds:  0

Writing A.1.node.
Writing A.1.ele.
Writing A.1.poly.
Writing A.1.edge.

Output milliseconds:  1
Total running milliseconds:  1

Statistics:

  Input vertices: 29
  Input segments: 29
  Input holes: 1

  Mesh vertices: 29
  Mesh triangles: 29
  Mesh edges: 58
  Mesh exterior boundary edges: 29
  Mesh interior boundary edges: 0
  Mesh subsegments (constrained edges): 29

Dune reported error: DGFException: could not find file
TMPDGFParser.AtxBzD.1.node prehaps something went wrong with
Tetgen/Triangle?

I am wondering how to treat this error message or how to import *.poly
files in general. I would be very thankful for any help or hints to face
the problem.

Best regards,
Wolfgang Giese