How to read latitude and longitude information from /GPSFix message in my bagfile?

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Hi friends, i am having a bagfile containing /GPSFix information. i want to read and publish its information using gpsd. for that i used gpsd_client tutorial.

I have given rosbag node port number for gpsd_client otherwise it is showing error. When i run gpsd_client it says "GPSD opened" but my gpsd_subscriber is not printing latitude and longitude information.

Please help me to solve this problem.

This is my gpsd_client

mit@mit-HP-Pro-3330-SFF:~/Desktop/Bagfiles$ rostopic info /GPSFix 
Type: gps_common/GPSFix

Publishers: None

Subscribers: 
 * /gps_subscriber (<a href="http://mit-HP-Pro-3330-SFF:33912/">http://mit-HP-Pro-3330-SFF:33912/</a>)


mit@mit-HP-Pro-3330-SFF:~/Desktop/Bagfiles$ rosrun gpsd_client gpsd_client _host:=localhost _port:=33912
[ INFO] [1374726241.992697318]: GPSd opened

This is my gpsd_subscriber

 mit@mit-HP-Pro-3330-SFF:~/Desktop/gps_test$ rosrun gpsd_subscriber gpsTest

This is my gpsd_subscriber source code

#include <iostream>
#include <ros/ros.h>
#include <sensor_msgs/NavSatFix.h>
#include <sensor_msgs/NavSatStatus.h>


using namespace sensor_msgs;

void callback(const NavSatFixConstPtr &fix) {

  if (fix->status.status == NavSatStatus::STATUS_NO_FIX) {
    std::cout << "Unable to get a fix on the location." << std::endl;
    return;
  }

  std::cout << "Current Latitude: " << fix->latitude << std::endl;
  std::cout << "Current Longitude " << fix->longitude << std::endl;

}

int main(int argc, char **argv) {
  ros::init(argc, argv, "gps_subscriber");
  ros::NodeHandle nh;

  ros::Subscriber gps_sub = nh.subscribe("/GPSFix", 1, callback);

  ros::spin();
  return 0;
}