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+Next File Transfer Protocol
+===========================
+
+Introduction
+------------
+
+Next File Transfer uses a simple protocol where a 2 character code defines
+a message type. 
+
+The following are standard compents of a message:
+
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | 5 ASCII digits making up a zero-padded number        |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | A stream of N bytes                                  |
+    +------------+------------------------------------------------------+
+
+
+Put File
+--------
+
+The format of the message from the client is:
+
+    +------------+------------------------------------------------------+
+    | PF         | Put file command                                     |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of filename                                   |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | The filename                                         |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of the data for the file                      |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | The data                                             |
+    +------------+------------------------------------------------------+
+
+The server responds with either:
+
+    +------------+------------------------------------------------------+
+    | OK         | The command completed OK                             |
+    +------------+------------------------------------------------------+
+
+or:
+
+    +------------+------------------------------------------------------+
+    | !E         | There was an error writing the file                  |
+    +------------+------------------------------------------------------+
+
+
+Get File
+--------
+
+The format of the message from the client is:
+
+    +------------+------------------------------------------------------+
+    | GF         | Get file command                                     |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of filename                                   |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | The filename                                         |
+    +------------+------------------------------------------------------+
+
+The server responds with either:
+
+    +------------+------------------------------------------------------+
+    | OK         | The command completed OK.  The file contents will    |
+    |            | follow.                                              |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of the following data                         |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | The data from from the file                          |
+    +------------+------------------------------------------------------+
+
+or:
+
+    +------------+------------------------------------------------------+
+    | !E         | There was an error reading the file                  |
+    +------------+------------------------------------------------------+
+
+
+Change Directory
+----------------
+
+The format of the message from the client is:
+
+    +------------+------------------------------------------------------+
+    | CD         | Change directory command                             |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of pathname                                   |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | The pathname                                         |
+    +------------+------------------------------------------------------+
+
+The server responds with either:
+
+    +------------+------------------------------------------------------+
+    | OK         | The command completed OK                             |
+    +------------+------------------------------------------------------+
+
+or:
+
+    +------------+------------------------------------------------------+
+    | !E         | There was an error changing to the directory         |
+    +------------+------------------------------------------------------+
+
+
+Create Directory
+----------------
+
+The format of the message from the client is:
+
+    +------------+------------------------------------------------------+
+    | MD         | Create directory command                             |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of pathname                                   |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | The pathname                                         |
+    +------------+------------------------------------------------------+
+
+The server responds with either:
+
+    +------------+------------------------------------------------------+
+    | OK         | The command completed OK                             |
+    +------------+------------------------------------------------------+
+
+or:
+
+    +------------+------------------------------------------------------+
+    | !E         | There was an error creating the directory            |
+    +------------+------------------------------------------------------+
+
+
+List Files
+----------
+
+The format of the message from the client is:
+
+    +------------+------------------------------------------------------+
+    | LS         | List files command                                   |
+    +------------+------------------------------------------------------+
+
+The server responds with either:
+
+    +------------+------------------------------------------------------+
+    | OK         | The command completed OK                             |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | The number of filenames                              |
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of filename 1                                 |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | Filename 1                                           |
+    +------------+------------------------------------------------------+
+    ... above 2 fields repeated ...
+    +------------+------------------------------------------------------+
+    | <NNNNN>    | Length of filename N                                 |
+    +------------+------------------------------------------------------+
+    | <N bytes>  | Filename N                                           |
+    +------------+------------------------------------------------------+
+
+or:
+
+    +------------+------------------------------------------------------+
+    | !E         | There was an error reading the directory             |
+    +------------+------------------------------------------------------+