diff --git a/BGL/test/BGL/test_bgl_read_write.cpp b/BGL/test/BGL/test_bgl_read_write.cpp
index 1ae5b23a6eb..c3f86c6c3d4 100644
--- a/BGL/test/BGL/test_bgl_read_write.cpp
+++ b/BGL/test/BGL/test_bgl_read_write.cpp
@@ -139,11 +139,11 @@ void test_bgl_OFF(const char* filename)
 
   // write with PM
   {
-    ok = CGAL::write_polygon_mesh("tmp.off", fg);
+    ok = CGAL::write_polygon_mesh("tmp.obj.off", fg);
     assert(ok);
 
     Mesh fg2;
-    ok = CGAL::read_polygon_mesh("tmp.off", fg2);
+    ok = CGAL::read_polygon_mesh("tmp.obj.off", fg2);
     assert(ok);
     assert(are_equal_meshes(fg, fg2));
   }
@@ -896,4 +896,3 @@ int main(int argc, char** argv)
 #endif
   return EXIT_SUCCESS;
 }
-//@todo add some tests for read_polygon_mesh"XXX.off.obj"
diff --git a/Point_set_3/include/CGAL/Point_set_3/point_set_io.h b/Point_set_3/include/CGAL/Point_set_3/point_set_io.h
index 3de2cf4a0d3..62c8515f04a 100644
--- a/Point_set_3/include/CGAL/Point_set_3/point_set_io.h
+++ b/Point_set_3/include/CGAL/Point_set_3/point_set_io.h
@@ -14,6 +14,7 @@
 
 #include <string>
 #include <CGAL/Point_set_3/IO.h>
+#include <CGAL/IO/polygon_soup_io.h>
 
 
 namespace CGAL {
@@ -26,20 +27,22 @@ template <typename Point,
 bool read_point_set(const std::string& fname,
                     CGAL::Point_set_3<Point, Vector>& ps)
 {
-  if (fname.find(".xyz") != std::string::npos) {
+  const std::string ext = IO::internal::get_file_extension(fname);
+
+  if (ext=="xyz") {
     return read_XYZ(fname, ps);
   }
 
-  if (fname.find(".off") != std::string::npos) {
+  if (ext == "off") {
     return read_OFF(fname, ps);
   }
 
-  if (fname.find(".ply") != std::string::npos) {
+  if (ext =="ply") {
     return read_PLY(fname, ps);
   }
 
 #ifdef CGAL_LINKED_WITH_LASLIB
-  if (fname.find(".las") != std::string::npos) {
+  if (ext == "las") {
     return read_LAS(fname, ps);
   }
 #endif
@@ -63,20 +66,21 @@ template <typename Point,
 bool write_point_set(const std::string& fname,
                     CGAL::Point_set_3<Point, Vector>& ps)
 {
-  if (fname.find(".xyz") != std::string::npos) {
+  const std::string ext = IO::internal::get_file_extension(fname);
+  if (ext == "xyz") {
     return write_XYZ(fname, ps);
   }
 
-  if (fname.find(".off") != std::string::npos) {
+  if (ext == "off") {
     return write_OFF(fname, ps);
   }
 
-  if (fname.find(".ply") != std::string::npos) {
+  if (ext == "ply") {
     return write_PLY(fname, ps);
   }
 
 #ifdef CGAL_LINKED_WITH_LASLIB
-  if (fname.find(".las") != std::string::npos) {
+  if (ext == "las") {
     return write_LAS(fname, ps);
   }
 #endif
diff --git a/Point_set_processing_3/include/CGAL/IO/read_points.h b/Point_set_processing_3/include/CGAL/IO/read_points.h
index 0b9d16140ca..80478c0f45d 100644
--- a/Point_set_processing_3/include/CGAL/IO/read_points.h
+++ b/Point_set_processing_3/include/CGAL/IO/read_points.h
@@ -54,20 +54,21 @@ bool read_points(const std::string& fname,
                     OutputIterator output,
                     const NamedParameters& np)
 {
-  if (fname.find(".xyz") != std::string::npos) {
+  const std::string ext = IO::internal::get_file_extension(fname);
+  if (ext == "xyz") {
     return read_XYZ<OutputIteratorValueType>(fname, output, np);
   }
 
-  if (fname.find(".off") != std::string::npos) {
+  if (ext == "off") {
     return read_OFF<OutputIteratorValueType>(fname, output, np);
   }
 
-  if (fname.find(".ply") != std::string::npos) {
+  if (ext == "ply") {
     return read_PLY<OutputIteratorValueType>(fname, output, np);
   }
 
 #ifdef CGAL_LINKED_WITH_LASLIB
-  if (fname.find(".las") != std::string::npos) {
+  if (ext == "las") {
     return read_LAS<OutputIteratorValueType>(fname, output, np);
   }
 #endif
diff --git a/Point_set_processing_3/include/CGAL/IO/write_points.h b/Point_set_processing_3/include/CGAL/IO/write_points.h
index 872c21470e7..65accc1bf3c 100644
--- a/Point_set_processing_3/include/CGAL/IO/write_points.h
+++ b/Point_set_processing_3/include/CGAL/IO/write_points.h
@@ -62,20 +62,21 @@ bool write_points(const std::string& fname,
                     const CGAL_BGL_NP_CLASS& np)
                 #endif
                 {
-  if (fname.find(".xyz") != std::string::npos) {
+  const std::string ext = IO::internal::get_file_extension(fname);
+  if (ext == "xyz") {
     return write_XYZ(fname, points, np);
   }
 
-  if (fname.find(".off") != std::string::npos) {
+  if (ext == "off") {
     return write_OFF(fname, points, np);
   }
 
-  if (fname.find(".ply") != std::string::npos) {
+  if (ext == "ply") {
     return write_PLY(fname, points, np);
   }
 
 #ifdef CGAL_LINKED_WITH_LASLIB
-  if (fname.find(".las") != std::string::npos) {
+  if (ext == "las") {
     return write_LAS(fname, points, np);
   }
 #endif