title: Android , Read in binary data and write it to file
body: <p>Im trying to read in image file from a server , with the code below . It keeps going into the exception. I know the correct number of bytes are being sent as I print them out when received. Im sending the image file from python like so</p>
  
  <pre><code>#open the image file and read it into an object
          imgfile = open (marked_image, 'rb')  
          obj = imgfile.read()
  
         #get the no of bytes in the image and convert it to a string
          bytes = str(len(obj))
  
  
          #send the number of bytes
          self.conn.send( bytes + '\n')
  
  
  
  
          if self.conn.sendall(obj) == None:
              imgfile.flush()
              imgfile.close()
              print 'Image Sent'
          else:
              print 'Error'
  </code></pre>
  
  <p>Here is the android part , this is where I'm having the problem. Any suggestions on the best way to go about receiving the image and writing it to a file ?</p>
  
  <pre><code>//read the number of bytes in the image
         String noOfBytes =  in.readLine();
  
  
         Toast.makeText(this, noOfBytes, 5).show();
  
         byte bytes [] = new byte [Integer.parseInt(noOfBytes)];
  
         //create a file to store the retrieved image
         File photo = new File(Environment.getExternalStorageDirectory(),  "PostKey.jpg");
  
         DataInputStream dis = new DataInputStream(link.getInputStream());
         try{
  
  
          os =new FileOutputStream(photo);
  
          byte buf[]=new byte[1024];
  
          int len;
  
          while((len=dis.read(buf))&gt;0)
          os.write(buf,0,len);
  
          Toast.makeText(this, "File recieved", 5).show();
  
          os.close();
          dis.close();
         }catch(IOException e){
  
             Toast.makeText(this, "An IO  Error Occured", 5).show();
         }
  </code></pre>
  
  <p>EDIT: I still cant seem to get it working. I have been at it since and the result of all my efforts have either resulted in a file that is not the full size or else the app crashing. I know the file is not corrupt before sending server side. As far as I can tell its definitely sending too as the send all method in python sends all or throws an exception in the event of an error and so far it has never thrown an exception. So the client side is messed up . I have to send the file from the server so I cant use the suggestion suggested by Brian . </p>