diff --git a/owlps-positioning/src/inputcsv.cc b/owlps-positioning/src/inputcsv.cc
index c4e8d8a..d9d05f4 100644
--- a/owlps-positioning/src/inputcsv.cc
+++ b/owlps-positioning/src/inputcsv.cc
@@ -17,24 +17,18 @@ using std::tr1::unordered_map ;
 
 
 /**
- * This function reads the next Request in the CSV input file. Blank
- * lines and lines containing only spaces are skipped.
+ * This function fills the current Request from the CSV input file.
+ * Blank lines and lines containing only spaces are skipped until a line
+ * containing a request is found.
  *
- * #file should be opened before proceeding requests; otherwise,
- * #current_request is \link Request::clear() cleared\endlink and a
- * blank Request is returned. The file must be valid,
- * semicolon-separated (\em not comma-separated).
- *
- * @return The read Request, or a blank Request in case of error (file
- * not opened, end of file, invalid field or wrong number of fields in
- * the line).
+ * @returns \em true if #current_request was correctly filled.
+ * @returns \em false in case of error (file not opened, end of file,
+ * invalid field or wrong number of fields in the line).
  */
-const Request& InputCSV::get_next_request()
+bool InputCSV::fill_current_request()
 {
-  clear_current_request() ;
-
   if (! file.next_line()) // End of file or error
-    return *current_request ;
+    return false ;
   ++current_line_nb ;
 
   // Read Mobile MAC field
@@ -43,13 +37,13 @@ const Request& InputCSV::get_next_request()
     {
       if (Configuration::is_configured("verbose"))
         cerr << "InputCSV: cannot read mac_mobile.\n" ;
-      return *current_request ;
+      return false ;
     }
   PosUtil::to_upper(mac_mobile) ;
 
   if (! Configuration::bool_value("positioning.accept-new-mobiles") &&
       ! Stock::mobile_exists(mac_mobile))
-    return *current_request ;
+    return false ;
 
   const Mobile &mobile = Stock::find_create_mobile(mac_mobile) ;
   current_request->set_mobile(&mobile) ;
@@ -59,11 +53,10 @@ const Request& InputCSV::get_next_request()
   uint16_t type_r ;
   if (! file.read_field(type_r))
     {
-      // Wrong number of fields: blank current request
-      current_request->clear() ;
+      // Wrong number of fields
       if (Configuration::is_configured("verbose"))
         cerr << "InputCSV: cannot read type.\n" ;
-      return *current_request ;
+      return false ;
     }
   type = type_r ;
   current_request->set_type(type) ;
@@ -72,11 +65,10 @@ const Request& InputCSV::get_next_request()
   Timestamp timestamp ;
   if (! file.read_timestamp(timestamp))
     {
-      // Wrong number of fields: blank current request
-      current_request->clear() ;
+      // Wrong number of fields
       if (Configuration::is_configured("verbose"))
         cerr << "InputCSV: cannot read timestamp.\n" ;
-      return *current_request ;
+      return false ;
     }
   current_request->set_time_sent(timestamp) ;
 
@@ -84,11 +76,10 @@ const Request& InputCSV::get_next_request()
   Point3D position ;
   if (! file.read_point3d(position))
     {
-      // Wrong number of fields: blank current request
-      current_request->clear() ;
+      // Wrong number of fields
       if (Configuration::is_configured("verbose"))
         cerr << "InputCSV: cannot read coordinates.\n" ;
-      return *current_request ;
+      return false ;
     }
 
   // Read direction field
@@ -96,11 +87,10 @@ const Request& InputCSV::get_next_request()
   int direction_int ;
   if (! file.read_field(direction_int))
     {
-      // Wrong number of fields: blank current request
-      current_request->clear() ;
+      // Wrong number of fields
       if (Configuration::is_configured("verbose"))
         cerr << "InputCSV: cannot read direction.\n" ;
-      return *current_request ;
+      return false ;
     }
   if (direction_int != 0)
     direction = direction_int ;
@@ -114,11 +104,10 @@ const Request& InputCSV::get_next_request()
       int ss ;
       if (! file.read_field(ss))
         {
-          // Wrong number of fields: blank current request
-          current_request->clear() ;
+          // Wrong number of fields
           if (Configuration::is_configured("verbose"))
             cerr << "InputCSV: cannot read mac_ap.\n" ;
-          return *current_request ;
+          return false ;
         }
       PosUtil::to_upper(mac_ap) ;
 
@@ -131,10 +120,7 @@ const Request& InputCSV::get_next_request()
       measurements[mac_ap].add_ss(ss) ;
     }
   if (measurements.empty())
-    {
-      current_request->clear() ;
-      return *current_request ;
-    }
+    return false ;
   current_request->set_measurements(measurements) ;
 
   // Calibration request?
@@ -152,5 +138,5 @@ const Request& InputCSV::get_next_request()
   else if (position)
     current_request->set_real_position(position) ;
 
-  return *current_request ;
+  return true ;
 }
diff --git a/owlps-positioning/src/inputcsv.hh b/owlps-positioning/src/inputcsv.hh
index 9310f51..de75abe 100644
--- a/owlps-positioning/src/inputcsv.hh
+++ b/owlps-positioning/src/inputcsv.hh
@@ -16,6 +16,12 @@ class InputCSV: public InputMedium
 protected:
   CSVFileReader file ;
 
+  /** @name Operations */
+  //@{
+  /// Reads data & fills the current request
+  bool fill_current_request(void) ;
+  //@}
+
 public:
   InputCSV(const std::string &filename):
     file(filename) {}
@@ -28,12 +34,6 @@ public:
   bool eof(void) const ;
   //@}
 
-  /** @name Operations */
-  //@{
-  /// Reads the next request
-  const Request& get_next_request(void) ;
-  //@}
-
   /** @name Operators */
   //@{
   operator bool(void) const ;
diff --git a/owlps-positioning/src/inputmedium.cc b/owlps-positioning/src/inputmedium.cc
index e424633..227df64 100644
--- a/owlps-positioning/src/inputmedium.cc
+++ b/owlps-positioning/src/inputmedium.cc
@@ -23,6 +23,45 @@ InputMedium::~InputMedium()
 /* *** Operations *** */
 
 
+/**
+ * Reads a Request, increments current_line_nb, updates #current_request
+ * and returns it.
+ *
+ * The input medium should be ready to be read before precessing
+ * requests; otherwise, #current_request is \link Request::clear()
+ * cleared\endlink and a blank Request is returned.
+ *
+ * @return The Request read, or an empty Request in case of error or
+ * EOF (note that when casted in bool, an empty Request is \em false,
+ * see Request::operator bool()).
+ */
+const Request& InputMedium::get_next_request()
+{
+  clear_current_request() ;
+
+  if (! fill_current_request())
+    {
+      clear_current_request() ;
+      return *current_request ;
+    }
+
+  return *current_request ;
+}
+
+
+void InputMedium::clear_current_request()
+{
+  if (dynamic_cast<CalibrationRequest*>(current_request) == NULL)
+    current_request->clear() ;
+  else
+    {
+      delete current_request ;
+      current_request = NULL ;
+      current_request = new Request() ;
+    }
+}
+
+
 void InputMedium::
 current_request_to_calibration_request(
   const ReferencePoint *const reference_point,
@@ -47,16 +86,3 @@ current_request_to_calibration_request(
                            direction, request_type) ;
   delete tmp ;
 }
-
-
-void InputMedium::clear_current_request()
-{
-  if (dynamic_cast<CalibrationRequest*>(current_request) == NULL)
-    current_request->clear() ;
-  else
-    {
-      delete current_request ;
-      current_request = NULL ;
-      current_request = new Request() ;
-    }
-}
diff --git a/owlps-positioning/src/inputmedium.hh b/owlps-positioning/src/inputmedium.hh
index 93f11b6..ccf29ad 100644
--- a/owlps-positioning/src/inputmedium.hh
+++ b/owlps-positioning/src/inputmedium.hh
@@ -18,6 +18,12 @@ protected:
   /// Number of the current line proceeded
   unsigned long current_line_nb ;
 
+  /** @name Operations */
+  //@{
+  /// Reads data & fills the current request
+  virtual bool fill_current_request(void) = 0 ;
+  //@}
+
 public:
   InputMedium(void) ;
 
@@ -43,14 +49,7 @@ public:
   //@{
 
   /// Reads the next request
-  /**
-   * Reads a Request, increments current_line_nb, updates #current_request
-   * and returns it.
-   * @return The Request read, or an empty Request in case of error or
-   * EOF (note that when casted in bool, an empty Request is \em false,
-   * see Request::operator bool()).
-   */
-  virtual const Request& get_next_request(void) = 0 ;
+  const Request& get_next_request(void) ;
 
   /// Converts #current_request into a CalibrationRequest
   void current_request_to_calibration_request(
diff --git a/owlps-positioning/src/inputudpsocket.cc b/owlps-positioning/src/inputudpsocket.cc
index dafe816..4351308 100644
--- a/owlps-positioning/src/inputudpsocket.cc
+++ b/owlps-positioning/src/inputudpsocket.cc
@@ -72,22 +72,16 @@ bool InputUDPSocket::close_socket()
 
 
 /**
- * This function reads the next Request in the UDP input socket.
- * It cannot read calibration requests.
+ * This function fills the current Request from the UDP input socket.
  *
- * #sockfd should be opened before processing requests; otherwise,
- * #current_request is \link Request::clear() cleared\endlink and a
- * blank Request is returned.
- *
- * @return The read Request, or a blank Request in case of error (socket
- * not opened, bad packet format).
+ * @returns \em true if #current_request was correctly filled.
+ * @returns \em false in case of error (socket not opened, bad packet
+ * format).
  */
-const Request& InputUDPSocket::get_next_request()
+bool InputUDPSocket::fill_current_request()
 {
-  clear_current_request() ;
-
   if (eof())
-    return *current_request ;
+    return false ;
 
   struct sockaddr_in client; // UDP client structure
   socklen_t client_len = sizeof(client) ; // Size of clients
@@ -98,8 +92,8 @@ const Request& InputUDPSocket::get_next_request()
                            (struct sockaddr *) &client, &client_len) ;
   if (nread <= 0)
     {
-      cerr << "No request received!" << endl ;
-      return *current_request ;
+      cerr << "InputUDPSocket: No request received!" << endl ;
+      return false ;
     }
 
   // Endianess conversions
@@ -113,7 +107,7 @@ const Request& InputUDPSocket::get_next_request()
 
   if (! Configuration::bool_value("positioning.accept-new-mobiles") &&
       ! Stock::mobile_exists(mac_mobile))
-    return *current_request ;
+    return false ;
 
   const Mobile &mobile = Stock::find_create_mobile(mac_mobile) ;
   current_request->set_mobile(&mobile) ;
@@ -139,8 +133,7 @@ const Request& InputUDPSocket::get_next_request()
       if (nread <= 0)
         {
           cerr << "No request info received!" << endl ;
-          current_request->clear() ;
-          return *current_request ;
+          return false ;
         }
       string mac_ap(
         owl_mac_bytes_to_string(request_info.ap_mac_addr_bytes)) ;
@@ -156,10 +149,7 @@ const Request& InputUDPSocket::get_next_request()
                                   (request_info.antenna_signal_dbm)) ;
     }
   if (measurements.empty())
-    {
-      current_request->clear() ;
-      return *current_request ;
-    }
+    return false ;
   current_request->set_measurements(measurements) ;
 
   // Calibration request?
@@ -198,5 +188,5 @@ const Request& InputUDPSocket::get_next_request()
   else if (position)
     current_request->set_real_position(position) ;
 
-  return *current_request ;
+  return true ;
 }
diff --git a/owlps-positioning/src/inputudpsocket.hh b/owlps-positioning/src/inputudpsocket.hh
index eff21f0..a3a6450 100644
--- a/owlps-positioning/src/inputudpsocket.hh
+++ b/owlps-positioning/src/inputudpsocket.hh
@@ -14,6 +14,15 @@ protected:
   //@{
   /// Initialises the socket
   bool init_socket(void) ;
+  /// Reads data & fills the current request
+  /**
+   * This function fills the current Request from the data read from
+   * the input medium.
+   *
+   * @returns \em true if #current_request was correctly filled.
+   * @returns \em false in case of error.
+   */
+  bool fill_current_request(void) ;
   //@}
 
 public:
@@ -29,8 +38,6 @@ public:
 
   /** @name Operations */
   //@{
-  /// Reads the next request
-  const Request& get_next_request(void) ;
   /// Closes the socket
   bool close_socket(void) ;
   //@}