Any Programmers around here?

#include "stdafx.h"
#include <windows.h>

#include <winbase.h>
#include <stdlib.h>
#include <conio.h>

int main(void)
{

	
    unsigned long int revs=0;
    LARGE_INTEGER total_time,diff_time,start_time,end_time,TICKS_PER_SECOND;
	char c=0;
	FILE *outp;

	QueryPerformanceFrequency(&TICKS_PER_SECOND);

	total_time.QuadPart=0;
	outp=fopen("output.csv","a");
	fflush(stdin);
	printf("QPC Freq: %I64d\n",TICKS_PER_SECOND.QuadPart);
	

	printf("Press any key to begin capturing.\n");
	
    
	getch();

	printf("Capturing counts to output.csv, press 'x' to quit...");

    QueryPerformanceCounter(&start_time);

	while(c!='x')
	{
		if(kbhit())
		{
		
		   QueryPerformanceCounter(&end_time);
		   diff_time.QuadPart=end_time.QuadPart-start_time.QuadPart;
		   total_time.QuadPart+=diff_time.QuadPart;
		   QueryPerformanceCounter(&start_time);
		   revs++;
		   fprintf(outp,"%ld,%I64d,%I64d,\n",revs,total_time.QuadPart,diff_time.QuadPart);
		   c=getch();
		}
		
	}

	fclose(outp);

	printf("\n\nTotal of %ld revolutions were counted!\n",revs);
	getch();

     return EXIT_SUCCESS;
}