Android - Write byte array to OutputStreamWriter
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I have an application that uploads photos through a web service.  In the past, I loaded a file into a stream, and converted to Base64.  Then I posted the resulting string through the write() method of an OutputStreamWriter.  Now, the web service has changed, and it expects multipart/form-data and it does not expect Base64.  

So somehow I need to post the chararters of this file as is without conversion.  I'm sure I'm close, but all I ever get is a content lengh underflow or overflow.  The odd thing is that in the debugger I can see that my buffer length is the same length as the string I'm posting.  Here's what I'm doing and hopefully enough code:

    // conn is my connection
    OutputStreamWriter dataStream = new OutputStreamWriter(conn.getOutputStream());
                  
    // c is my file
    int bytesRead = 0;
    long bytesAvailable = c.length();
               
    while (bytesAvailable > 0) {
       byte[] buffer = new byte[Math.min(12288, (int)bytesAvailable)];
       bytesRead = fileInputStream.read(buffer, 0, Math.min(12288, (int)bytesAvailable));
                   
       // assign the string if needed.
       if (bytesRead > 0) {
          bytesAvailable = fileInputStream.available();
          
          // I've tried many encoding types here.
          String sTmp = new String(buffer, "ISO-8859-1");
          // HERE'S the issue.  I can't just write the buffer,
          dataStream.write(sTmp);
          dataStream.flush();
    // Yes there's more code, but this should be enough to show why I don't know what I'm doing!