Cant copy the whole text file to char array - c++

Question

I am trying to copy a whole text file into char array using fstream but even upon increasing the size of the array it reads the text file to same limit .i am bount to save it in a char array and it will be good if it is not a dynamic one ??? any solution please ...
// smallGrams.cpp : Defines the entry point for the console application.
//
//#include "stdafx.h"
#include<iostream>
using namespace std;
#include<string>
#include<fstream>
void readInput(const char* Path);
void removePunctucationMarks();
void removeSpacing();
void insertDots();
char * getText();
void generateUnigrams();
void generateBigrams();
void generateTrigrams();
double validateSentance(string str);
string sentenceCreation(int position);
int main()
{
char *path="alice.txt";
readInput(path);
return 0;
}
void readInput(const char* Path)
{
ifstream infile;
infile.open(Path);
if(!infile.fail())
cout<<"File opened successfully"<<endl;
else
cout<<"File failed to open"<<endl;
int arrSize=100000000;
char *arr=new char[arrSize];
int i=0;
while(!infile.eof()&&i<arrSize)
{
infile.get(arr[i]);
i++;
}
arr[i-1]='\0';
for(short i=0;i<arrSize&&arr[i]!='\0';i++)
{
cout<<arr[i];
}
}

Answer 1

This is a C style solution that works. It checks the file size and then allocate the necessary memory for the array and reads all the content of the file in one call. The fread() call returns the number of bytes you requested or an error has ocurred (check fread() reference)
# include <cstring>
# include <cstdlib>
# include <cstdio>
int main(int argc, char *argv[]) {
char *data;
int data_len;
FILE *fd;
fd = fopen ("file.txt", "r");
if (fd == NULL) {
// error
return -1;
}
fseek (fd , 0 , SEEK_END);
data_len = ftell (fd);
rewind (fd);
data = (char *) malloc ((data_len + 1) * sizeof (char));
memset (data, data_len + 1, NULL);
if (fread (data, sizeof (char), data_len, fd) != data_len) {
// error
return -1;
}
printf ("%s\n", data);
fclose (fd);
free (data);
return 0;
}

Answer 2

Here with a simple doubling method...
#include<iostream>
#include<string>
#include<fstream>
#include <cstdint>
#include <cstring>
using namespace std;
void readInput(const char* Path)
{
ifstream infile;
infile.open(Path);
if(!infile.fail())
cout<<"File opened successfully"<<endl;
else{
cout<<"File failed to open"<<endl;
return;
}
int capacity=1000;
char *arr=new char[capacity];
char *temp;
int i=0;
while(infile >> arr[i])
{
i++;
if ( i >= capacity ) {
temp = new char[capacity*2];
std::memcpy(temp , arr, capacity);
delete [] arr;
arr = temp;
capacity *=2;
}
}
}
int main()
{
char *path="alice.txt";
readInput(path);
return 0;
}

Answer 3

The error could when you read and display the array content using the for loop and not on reading the data from file.
Use int instead of short in for loop, as short can increment upto 32768, only.