using System;
using System.IO;

public class CopyApp {

  public static void Main(string[] args) {
    FileInfo   inFile  = new FileInfo(args[0]),
               outFile = new FileInfo(args[1]);
    FileStream inStr   = inFile.OpenRead(),     
               outStr  = outFile.OpenWrite();   
    int c;
   do{                                          
      c = inStr.ReadByte();                     
      if(c != -1) outStr.WriteByte((byte)c);
   } while (c != -1);  

   inStr.Close();                               
   outStr.Close();
 }
}

 
 
 
 
 
 
 
 
Binary FileStream objects 
for input and output.
 
In a loop, read a byte from inStr
and write the byte to outStr.
 
 
 
Close both streams.