1. Introduction

   This document updates the File Transfer Protocol (FTP) [3].  Four new
   commands are added: "SIZE", "MDTM", "MLST", and "MLSD".  The existing
   command "REST" is modified.  Of those, the "SIZE" and "MDTM"
   commands, and the modifications to "REST" have been in wide use for
   many years.  The others are new.

   These commands allow a client to restart an interrupted transfer in
   transfer modes not previously supported in any documented way, and to
   obtain a directory listing in a machine friendly, predictable,
   format.

   An optional structure for the server's file store (NVFS) is also
   defined, allowing servers that support such a structure to convey
   that information to clients in a standard way, thus allowing clients
   more certainty in constructing and interpreting pathnames.