diff --git a/owlps-positioning/src/outputtcpsocketevaal.cc b/owlps-positioning/src/outputtcpsocketevaal.cc
index 68b0d24..ebec47e 100644
--- a/owlps-positioning/src/outputtcpsocketevaal.cc
+++ b/owlps-positioning/src/outputtcpsocketevaal.cc
@@ -123,8 +123,9 @@ area_of_interest_number(const Point3D &position) const
  */
 bool OutputTCPSocketEvAAL::send_data(const string &data) const
 {
-  ssize_t nsent = send(sockfd, data.c_str(), data.size(), 0) ;
-  if (nsent != static_cast<ssize_t>(data.size()))
+  unsigned int data_len = data.size() + 1 ; // +1 for the '\0'
+  ssize_t nsent = send(sockfd, data.c_str(), data_len, 0) ;
+  if (nsent != static_cast<ssize_t>(data_len))
     {
       perror("Error sending result data through the TCPEvAAL socket") ;
       return false ;
diff --git a/owlps-positioning/src/outputudpsocket.cc b/owlps-positioning/src/outputudpsocket.cc
index ebc8350..1984e04 100644
--- a/owlps-positioning/src/outputudpsocket.cc
+++ b/owlps-positioning/src/outputudpsocket.cc
@@ -45,10 +45,11 @@ bool OutputUDPSocket::init_socket()
  */
 bool OutputUDPSocket::send_data(const string &data) const
 {
-  ssize_t nsent = sendto(sockfd, data.c_str(), data.size(), 0,
+  unsigned int data_len = data.size() + 1 ; // +1 for the '\0'
+  ssize_t nsent = sendto(sockfd, data.c_str(), data_len, 0,
                          (struct sockaddr *) &server_info,
                          sizeof(server_info)) ;
-  if (nsent != static_cast<ssize_t>(data.size()))
+  if (nsent != static_cast<ssize_t>(data_len))
     {
       perror("Error sending result data through the UDP socket") ;
       return false ;