copy whole of a file into memory using mmap

i want to copy whole of a file to memory using mmap in C.i write this code:

#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <errno.h>
int main(int arg, char *argv[])
{
    char c ;
    int numOfWs = 0 ;
    int numOfPr = 0 ;
    int numberOfCharacters ;
    int i=0;
    int k;
    int pageSize = getpagesize();
    char *data;
    float wsP = 0;
    float prP = 0;
    int fp = open("2.txt", O_RDWR);
    data = mmap((caddr_t)0, pageSize, PROT_READ, MAP_SHARED, fp,pageSize);
    printf("%s\n", data);
    exit(0);
}

when i execute the code i get the Bus error message. next, i want to iterate this copied file and do some thing on it. how can i copy the file correctly?