[vtkusers] Writing .vtk files

[Lydia Yahia-Cherif]

Hi everybody,
I want to create a 3D model starting from contours. I used the Marching
cubes and
the following sequence is the end part of my program.  
 
  vtkPolyDataWriter *writer=vtkPolyDataWriter::New();
     writer->SetInput(stripper->GetOutput());
     writer->SetFileName("mesh.vtk");
     writer->SetFileType(2);
 
The problem is that the file mesh.vtk is not created. Is there anything that
has to be added ?? I can't find it in the examples.
Thanks for the reply
Lydia