DUNE/Hardware/SocketCAN: Suppress unused result warning.

src/DUNE/Hardware/SocketCAN.cpp

@@ -171,25 +171,27 @@ namespace DUNE
     size_t
     SocketCAN::doWrite(const uint8_t* bfr, size_t size) { // TODO: Add exceptions
 #if defined(DUNE_OS_LINUX)
+      ssize_t bytes_written;
       switch(can_frame_type) {
         case CAN_BASIC_SFF:
         case CAN_BASIC_EFF:
           struct can_frame frame;
           frame.can_dlc = size;
           frame.can_id = cantxid;
           memcpy(frame.data, bfr, size);
-          ::write(m_can_socket, &frame, CAN_MTU);
+          bytes_written = ::write(m_can_socket, &frame, CAN_MTU);
         break;
         case CAN_FD:
           struct canfd_frame fdframe;
           fdframe.len = size;
           fdframe.can_id = cantxid;
           memcpy(fdframe.data, bfr, size);
-          ::write(m_can_socket, &fdframe, CANFD_MTU);
+          bytes_written = ::write(m_can_socket, &fdframe, CANFD_MTU);
         break;
         default:
           throw Error("Frame type not recognized", System::Error::getLastMessage());
       }
+      (void)bytes_written;
       return size;
 #else
       throw Error("Could not complete", "Unimplemented");