cvSetTrackbarPos exits as soon as you move the trackbar

#include<opencv/highgui.h>
# include <opencv/cv.h>
# include <iostream>
# include <cstdlib>

using namespace std;

intg_slider_position = 0;
intg_point = 0;

CvCapture*g_capture=NULL;

// Callback when moving the track bar
void onTrackbarSlide(intpos) {
    cvSetCaptureProperty(g_capture,
        CV_CAP_PROP_POS_AVI_RATIO,
        pos
    );
    cvSetTrackbarPos("Position", "Example 3", pos);

}
int main (int argc, char**argv)
{
    const char Wname [ ] = "Example 3";
    cvNamedWindow(Wname, CV_WINDOW_AUTOSIZE);
    g_capture=cvCreateFileCapture(argv[1]);
    // To represent the current position in percentage 100
    int frames = 100;
    // Because I used the track bar according to the number of frames
    (int) cvGetCaptureProperty(
        g_capture,
        CV_CAP_PROP_FRAME_COUNT
    );
    IplImage* frame;

    if(frames!=0){
        // Create Trackbar
        cvCreateTrackbar(
            "Position",
            Wname,
            &g_slider_position,
            frames,
            onTrackbarSlide
        );
    }
    while(1){
        frame = cvQueryFrame(g_capture);
        if(!frame)break;
        cvShowImage (Wname, frame);
        charc = cvWaitKey (1000);
        if(c==27)break;
        // Does not work properly when comment is removed
//      cvSetTrackbarPos ("Position", Wname, (int) cvGetCaptureProperty(g_capture, CV_CAP_PROP_FRAME_COUNT)*100);
    }
    return 0;
}