src/talker.cpp
bool changeString(beginner_tutorials::change_string::Request &req,
        beginner_tutorials::change_string::Response &res) {
    strMsg = req.input;
    res.output = strMsg;             // modify the output string
    /* Info logger level message */
    ROS_INFO_STREAM("Modified the base output string message");
    return true;
}
/**
  * @brief      changeString
  *
  * @param      req     request message
  * @param      res     response messsge
  *
  * @return     boolean value after successful callback
  */
@brief      changeString
@param      req     request message
@param      res     response messsge

@return     boolean value after successful callback
@brief changeString @param req request message @param res response messsge @return boolean value after successful callback
bool changeString(beginner_tutorials::change_string::Request &req,
        beginner_tutorials::change_string::Response &res) {
    strMsg = req.input;
    res.output = strMsg;             
    ROS_INFO_STREAM("Modified the base output string message");
    return true;
}
bool changeString ( beginner_tutorials :: change_string :: Request & req , beginner_tutorials :: change_string :: Response & res ) { strMsg = req . input ; res . output = strMsg ; ROS_INFO_STREAM ( " " ) ; return true ; }
@brief      changeString
 @param      req     request message
 @param      res     response messsge
@brief changeString @param req request message @param res response messsge
// modify the output string /* Info logger level message */