Why does this data stream end at byte 26?

I am still working on this bitmap I / O issue from a week ago. I got stuck again, so I decided to start with the I / OI type I was familiar with and make it more like what I needed relentlessly (which checks every byte (pixel) at a time and outputs to a file based on that byte ).

I started with a program that read and checked every character in a text file and output "Z" if it was above a certain threshold and output "A" if it was below it.

This program worked great, so I decided to change it from characters to bytes in the file.

Now I had problems with this. The first 26 (bytes 0-25) bytes of the file are correct, but the rest are 0 or -1, depending on whether I use ifstream.get()

or ifstream.read

.

The input file Input.FILE

was executed in a hex editor and just contains 0x00-0xFF

. It is 256 bytes long.

Code:

#include <iostream>
#include <fstream>
#include <vector>

using namespace std;

int main()
{
   ifstream sourcefile;
   ofstream output;
   ofstream output2;

   output.open("output.txt");
   output2.open("messages.txt");
   sourcefile.open("Input.FILE");

   vector<char> data(256);
   sourcefile.read(&data[0],256);
   sourcefile.seekg(0,ios::beg);

   for(int i = (int) 0x00 ; i < data.size() ; i++)
   {
      output2 << "Value data[" << i << "] = " << (int) data[i] << endl;

      if((int)data[i] < 0)
      {
         // since I can't make an unsigned char vector, I use this to convert
         // it to the correct number. Could this be the problem?
         data[i] = 256 + data[i];
         output2 << "less than zero." << endl;
      }

      if(data[i] > 64)
      {
         data[i] = 0xFF;
         output2 << "greater than 64, set to 0xFF." << endl;
      }
      else if(data[i] < 64)
      {
         data[i] = 0x00;
         output2 << "less than 64, set to 0x00." << endl;
      }
      else
      {
         // This is most likely pointless, but I didn't want to take a chance
         data[i] = 0x75;
         output2 << "neither greater nor less than 64? Set to 0x75." << endl;
      }

      output2 << endl;
   }

   output.write(&data[0],256);
}

      

        
        
        
      

    

Output (from message.txt

):

Note: data[0-25]

contain correct values

...
Value data [19] = 19 is less than 64, set to 0x00.
These values ​​[20] = 20 less than 64 are set to 0x00.
These values ​​[21] = 21 less than 64 are set to 0x00.
These values ​​[22] = 22 less than 64 are set to 0x00.
These values ​​[23] = 23 less than 64 are set to 0x00.
These values ​​[24] = 24 less than 64 are set to 0x00.
These values ​​[25] = 25 less than 64 are set to 0x00.
Data value [26] = 0 less than 64, set to 0x00.