diff --git a/Polygon_mesh_processing/examples/Polygon_mesh_processing/point_inside_example_OM.cpp b/Polygon_mesh_processing/examples/Polygon_mesh_processing/point_inside_example_OM.cpp
index 0a68b79b69a..d72781e7791 100644
--- a/Polygon_mesh_processing/examples/Polygon_mesh_processing/point_inside_example_OM.cpp
+++ b/Polygon_mesh_processing/examples/Polygon_mesh_processing/point_inside_example_OM.cpp
@@ -45,7 +45,7 @@ int main(int argc, char* argv[])
   OpenMesh::IO::read_mesh(mesh, filename);
   if (!CGAL::is_triangle_mesh(mesh))
   {
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
  
@@ -73,10 +73,10 @@ int main(int argc, char* argv[])
     if (res == CGAL::ON_BOUNDARY) { ++nb_boundary; }
   }
 
-  std::cerr << "Total query size: " << points.size() << std::endl;
-  std::cerr << "  " << nb_inside << " points inside " << std::endl;
-  std::cerr << "  " << nb_boundary << " points on boundary " << std::endl;
-  std::cerr << "  " << points.size() - nb_inside - nb_boundary << " points outside " << std::endl;
+  std::cout << "Total query size: " << points.size() << std::endl;
+  std::cout << "  " << nb_inside << " points inside " << std::endl;
+  std::cout << "  " << nb_boundary << " points on boundary " << std::endl;
+  std::cout << "  " << points.size() - nb_inside - nb_boundary << " points outside " << std::endl;
 
-  return 0;
+  return EXIT_SUCCESS;
 }
diff --git a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/sdf_values_example.cpp b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/sdf_values_example.cpp
index bc41ab82e9f..c9e34d8ec19 100644
--- a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/sdf_values_example.cpp
+++ b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/sdf_values_example.cpp
@@ -17,7 +17,7 @@ int main()
   Polyhedron mesh;
   std::ifstream input("data/cactus.off");
   if ( !input || !(input >> mesh) || mesh.empty() || ( !CGAL::is_triangle_mesh(mesh)) ) {
-    std::cout << "Input is not a triangle mesh" << std::endl;
+    std::cerr << "Input is not a triangle mesh" << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_OpenMesh_example.cpp b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_OpenMesh_example.cpp
index 5273f9b519b..726e7f80f64 100644
--- a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_OpenMesh_example.cpp
+++ b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_OpenMesh_example.cpp
@@ -29,7 +29,7 @@ int main(int argc, char** argv )
     OpenMesh::IO::read_mesh(mesh, "data/cactus.off");
  
   if (!CGAL::is_triangle_mesh(mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
   std::cout << "#F : " << num_faces(mesh) << std::endl;
diff --git a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_SM_example.cpp b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_SM_example.cpp
index 7c2d9cdc363..e820173c297 100644
--- a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_SM_example.cpp
+++ b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_SM_example.cpp
@@ -30,7 +30,7 @@ int main(int argc, char** argv )
     cactus >> mesh;
   }
   if (!CGAL::is_triangle_mesh(mesh)){
-    std::cout << "Input is not a triangle mesh" << std::endl;
+    std::cerr << "Input is not a triangle mesh" << std::endl;
     return EXIT_FAILURE;
   }
   typedef Mesh::Property_map<face_descriptor,double> Facet_double_map;
diff --git a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_example.cpp b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_example.cpp
index 254acb22031..9f3b15f4354 100644
--- a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_example.cpp
+++ b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_from_sdf_values_example.cpp
@@ -17,7 +17,7 @@ int main()
     Polyhedron mesh;
     std::ifstream input("data/cactus.off");
     if ( !input || !(input >> mesh) || mesh.empty()  || ( !CGAL::is_triangle_mesh(mesh))) {
-      std::cout << "Input is not a triangle mesh." << std::endl;
+      std::cerr << "Input is not a triangle mesh." << std::endl;
       return EXIT_FAILURE;
     }
 
diff --git a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_via_sdf_values_example.cpp b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_via_sdf_values_example.cpp
index 6dc494f07b2..5ff383b286b 100644
--- a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_via_sdf_values_example.cpp
+++ b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_via_sdf_values_example.cpp
@@ -17,7 +17,7 @@ int main()
     Polyhedron mesh;
     std::ifstream input("data/cactus.off");
     if ( !input || !(input >> mesh) || mesh.empty() || ( !CGAL::is_triangle_mesh(mesh)) ) {
-        std::cout << "Input is not a triangle mesh" << std::endl;
+        std::cerr << "Input is not a triangle mesh" << std::endl;
         return EXIT_FAILURE;
     }
 
diff --git a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_with_facet_ids_example.cpp b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_with_facet_ids_example.cpp
index 5d026280ac8..42f6fc3c3e1 100644
--- a/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_with_facet_ids_example.cpp
+++ b/Surface_mesh_segmentation/examples/Surface_mesh_segmentation/segmentation_with_facet_ids_example.cpp
@@ -40,7 +40,7 @@ int main()
     Polyhedron mesh;
     std::ifstream input("data/cactus.off");
     if ( !input || !(input >> mesh) || mesh.empty() || ( !CGAL::is_triangle_mesh(mesh)) ) {
-      std::cout << "Input is not a triangle mesh" << std::endl;
+      std::cerr << "Input is not a triangle mesh" << std::endl;
       return EXIT_FAILURE;
     }
 
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_OpenMesh.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_OpenMesh.cpp
index ffb1d32e70f..6a766f1b2c8 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_OpenMesh.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_OpenMesh.cpp
@@ -65,7 +65,7 @@ int main( int argc, char** argv )
     OpenMesh::IO::read_mesh(surface_mesh, "cube.off");
 
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_all_short_edges.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_all_short_edges.cpp
index 365ab7628b8..50db33eac18 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_all_short_edges.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_all_short_edges.cpp
@@ -23,7 +23,7 @@ int main( int argc, char** argv )
 {
   if (argc<3)
   {
-    std::cout << "Usage: " << argv[0] << " input.off minimal_edge_length [out.off]\n";
+    std::cerr << "Usage: " << argv[0] << " input.off minimal_edge_length [out.off]\n";
     return EXIT_FAILURE;
   }
 
@@ -33,7 +33,7 @@ int main( int argc, char** argv )
   double threshold = atof(argv[2]);
 
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrain_sharp_edges.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrain_sharp_edges.cpp
index 178a5a6d030..3fc158e1891 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrain_sharp_edges.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrain_sharp_edges.cpp
@@ -65,20 +65,20 @@ int main( int argc, char** argv )
   Surface_mesh surface_mesh;
 
   if (argc < 2){
-    std::cout << "Usage: " << argv[0] << " input.off [out.off]\n";
+    std::cerr << "Usage: " << argv[0] << " input.off [out.off]\n";
     return EXIT_FAILURE;
   }
 
   std::ifstream is(argv[1]);
   if(!is){
-    std::cout << "Filename provided is invalid\n";
+    std::cerr << "Filename provided is invalid\n";
     return EXIT_FAILURE;
   }
 
   is >> surface_mesh  ;
 
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
@@ -101,7 +101,7 @@ int main( int argc, char** argv )
   {
     halfedge_descriptor hd = halfedge(*eb,surface_mesh);
     if ( is_border(*eb,surface_mesh) ){
-      std::cout << "border" << std::endl;
+      std::cerr << "border" << std::endl;
       ++nb_sharp_edges;
       constraint_hmap[*eb]=true;
       constrained_edges[*eb]=std::make_pair(point(source(hd,surface_mesh),surface_mesh),
@@ -124,7 +124,7 @@ int main( int argc, char** argv )
   }
   cst_output.close();
 
-  std::cout << "# sharp edges = " << nb_sharp_edges << std::endl;
+  std::cerr << "# sharp edges = " << nb_sharp_edges << std::endl;
 
   // Contract the surface mesh as much as possible
   SMS::Count_stop_predicate<Surface_mesh> stop(0);
@@ -167,7 +167,7 @@ int main( int argc, char** argv )
     }
   }
   std::cout  << "OK\n";
-  std::cout << "# sharp edges = " << nb_sharp_edges << std::endl;
+  std::cerr << "# sharp edges = " << nb_sharp_edges << std::endl;
 
   std::cout << "Check that no removable edge has been forgotten..." << std::endl;
   r = SMS::edge_collapse(surface_mesh
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_polyhedron.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_polyhedron.cpp
index 6d5aa61efdf..ab632a46d9a 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_polyhedron.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_polyhedron.cpp
@@ -55,19 +55,19 @@ int main( int argc, char** argv )
   Surface_mesh surface_mesh;
 
   if (argc!=2){
-    std::cout << "Usage: " << argv[0] << " input.off\n";
+    std::cerr << "Usage: " << argv[0] << " input.off\n";
     return EXIT_FAILURE;
   }
 
   std::ifstream is(argv[1]);
   if(!is){
-    std::cout << "Filename provided is invalid\n";
+    std::cerr << "Filename provided is invalid\n";
     return EXIT_FAILURE;
   }
 
   is >> surface_mesh  ;
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_surface_mesh.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_surface_mesh.cpp
index 8f33627a1a5..1cc6ed45233 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_surface_mesh.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_constrained_border_surface_mesh.cpp
@@ -59,19 +59,19 @@ int main( int argc, char** argv )
   Surface_mesh surface_mesh;
 
   if (argc!=2){
-    std::cout << "Usage: " << argv[0] << " input.off\n";
+    std::cerr << "Usage: " << argv[0] << " input.off\n";
     return EXIT_FAILURE;
   }
 
   std::ifstream is(argv[1]);
   if(!is){
-    std::cout << "Filename provided is invalid\n";
+    std::cerr << "Filename provided is invalid\n";
     return EXIT_FAILURE;
   }
 
   is >> surface_mesh  ;
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
@@ -113,7 +113,7 @@ int main( int argc, char** argv )
       --nb_border_edges;
       if(constrained_halfedges[hd] != std::make_pair(surface_mesh.point(source(hd,surface_mesh)),
                                                      surface_mesh.point(target(hd,surface_mesh)))){
-        std::cout << "oops. send us a bug report\n";
+        std::cerr << "oops. send us a bug report\n";
       }
 
     }
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_enriched_polyhedron.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_enriched_polyhedron.cpp
index 68a449dac0d..769009c1dff 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_enriched_polyhedron.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_enriched_polyhedron.cpp
@@ -70,7 +70,7 @@ struct My_visitor : SMS::Edge_collapse_visitor_base<Surface_mesh>
   void OnCollected( Profile const&, boost::optional<double> const& )
   {
     ++ stats->collected ;
-    std::cout << "\rEdges collected: " << stats->collected << std::flush ;
+    std::cerr << "\rEdges collected: " << stats->collected << std::flush ;
   }                
   
   // Called during the processing phase for each edge selected.
@@ -86,8 +86,8 @@ struct My_visitor : SMS::Edge_collapse_visitor_base<Surface_mesh>
       ++ stats->cost_uncomputable ;
       
     if ( current == initial )
-      std::cout << "\n" << std::flush ;
-    std::cout << "\r" << current << std::flush ;
+      std::cerr << "\n" << std::flush ;
+    std::cerr << "\r" << current << std::flush ;
   }                
   
   // Called during the processing phase for each edge being collapsed.
@@ -124,7 +124,7 @@ int main( int argc, char** argv )
   
   std::ifstream is(argv[1]) ; is >> surface_mesh ;
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_polyhedron.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_polyhedron.cpp
index 918a9c6bc9b..91a39f8a056 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_polyhedron.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_polyhedron.cpp
@@ -26,7 +26,7 @@ int main( int argc, char** argv )
   
   std::ifstream is(argv[1]) ; is >> surface_mesh ;
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }
 
diff --git a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_surface_mesh.cpp b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_surface_mesh.cpp
index 0d1a610e24b..574b3f969c2 100644
--- a/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_surface_mesh.cpp
+++ b/Surface_mesh_simplification/examples/Surface_mesh_simplification/edge_collapse_surface_mesh.cpp
@@ -66,7 +66,7 @@ struct My_visitor : SMS::Edge_collapse_visitor_base<Surface_mesh>
   void OnCollected( Profile const&, boost::optional<double> const& )
   {
     ++ stats->collected ;
-    std::cout << "\rEdges collected: " << stats->collected << std::flush ;
+    std::cerr << "\rEdges collected: " << stats->collected << std::flush ;
   }                
   
   // Called during the processing phase for each edge selected.
@@ -82,8 +82,8 @@ struct My_visitor : SMS::Edge_collapse_visitor_base<Surface_mesh>
       ++ stats->cost_uncomputable ;
       
     if ( current == initial )
-      std::cout << "\n" << std::flush ;
-    std::cout << "\r" << current << std::flush ;
+      std::cerr << "\n" << std::flush ;
+    std::cerr << "\r" << current << std::flush ;
   }                
   
   // Called during the processing phase for each edge being collapsed.
@@ -120,7 +120,7 @@ int main( int argc, char** argv )
   
   std::ifstream is(argv[1]) ; is >> surface_mesh ;
   if (!CGAL::is_triangle_mesh(surface_mesh)){
-    std::cout << "Input geometry is not triangulated." << std::endl;
+    std::cerr << "Input geometry is not triangulated." << std::endl;
     return EXIT_FAILURE;
   }