[Boost-users] how to use input_filter to read data from a file?

hello all. I have a code that gets a line, encodes it in base64 and save it to a file and another part that opens the same file inorder to read the data, for some reason, the get function at line 99 returns an empty string. how can I solve this problem? complete code can be found at http://pastebin.com/f62d2fbf5 thanks