-------------------------------------------------------
 AC_FTP.EXE: file transfer protocol client application 
-------------------------------------------------------

This application is described in detail in Chapter 7, "Sample
Application and Library" in _Windows Sockets Network Programming_  
by Bob Quinn and Dave Shute, published by Addison-Wesley, Reading, MA  
ISBN: 0-201-63372-8

What it does: AC_FTP is a file transfer protocol client
 that uses asynchronous socket operation mode and utilizes many
 programming techniques described in detail throughout the book.
 It connects to an FTP server, sends commands and receives replies
 according to rfc959.txt">RFC 959 to get and put files,
 change directories, get file lists, delete files.

What it illustrates: The source code for AC_FTP illustrates
 many key aspects of WinSock application programming, including
 how to connect as a TCP client and as a server, how to maximize
 data throughput using sockets with asynchronous operation mode.
 It also demonstrates how to receive variable length data on a
 stream connection; this is often a problem since TCP (rfc793.txt">RFC 793
 and rfc1122.txt">RFC 1122) does not preserve packet
 boundaries. It also shows how to implement an application protocol--the
 FTP protocol--using a state machine; maintaining socket state
 is an important aspect of most network applications.

How to Use it: AC_FTP implements a subset of the FTP command
 set, and has buttons in the main dialog box for each of the commands
 available..

  - Start by pressing the "Connect" button, and fill
     in the destination hostname or IP address (the location of the
     FTP server), the user name and password.. Once the "Status"
     in upper right of the AC_FTP application window says "connected,"
     you can press the other buttons to issue FTP commands
  - The "DIR" button in the "Remote Working Directory"
     box.retrieves the remote file directory, and "DIR" in
     the "Local Working Directory" displays the file directory
     from the local disk. AC_FTP puts the file directory list into
     a temporary file called delete.me, and invokes the Windows notepad.exe
     to display it. You can leave several such directory file lists
     open for simultaneos viewing
  - The "CWD" buttons allow you move to different directories
     on the remote or local systems.
  - The "Put" and "Get" buttons send and receive
     files, respectively.
  - You can "Abort" any pending operation, "Close" the control 
     connection, or "Exit" the application at any time.

Known Problems: AC_FTP, as all other the sample applications,
 suffers from a user-hostile interface. User friendliness was sacrificed
 to minimize user interface code, and emphasize the network code.
 The most blatant user-hostile feature is the text in the status
 box that scrolls in the wrong direction. The method of displaying
 the file directories is less than ideal also, but calls for very
 little code. The CWD command does not allow you to move between
 disks on the local system.

File List: 
 AC_FTP\AC_FTP.DEF 
 AC_FTP\AC_FTP.ICO 
 AC_FTP\RESOURCE.H 
 AC_FTP\AC_FTP.H 
 AC_FTP\AC_FTP.MAK Makefile for 16-bit ac_ftp.exe 
 AC_FTP\AC_FTP32.MAK Makefile for 32.bit ac_ftp32.exe 
 AC_FTP\AC_FTP.RC 
 AC_FTP\FTP_DATA.C all routines for the data connection 
 AC_FTP\FTP_CTRL.C all routines for the control connection 
 AC_FTP\AC_FTP.C

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 NOTES:
--------

We used Microsoft Visual C++ enviroments (versions 1.52 for 16-bit,
and version 2.1 for 32-bit) to create most of the makefiles.
Unfortunately, because the paths are hard-coded in the file, you will
have to bring the project files (.mak) into the respective MS C++
environments to readjust things to the new directory, and even then
you will have to manually alter the project to access the library
files (the are in the root of the directory where you install the
samples).

All samples--including the sample DLL and static library--have a
number of other things in common:

  - They all have 32-bit versions, and all 32-bit version names
     end with "32" (16-bit versions don't have a number).
  - They use the WSAperror() function from #WINSOCKX">WINSOCKX.LIB
    to display error values and short descriptions when an unexpected
    error occurs.
  - They display error messages on any suspicious error condition.
     They don't hide errors, but report them whenever they occur. As
     we describe n a_c.htm">Appendix C: WinSock Error Reference,
     these error messages should appear only when a "user fixable
     error" occurs. If you get an error message from a sample
     application for a non user-fixable error, then this may
     indicate an anomoly in the WinSock implementation that your applications
     may need to deal with. We show you the errors on purpose, to make
     you aware of unexpected conditions.
  - They have a minimal user interface, and do not have help (.HLP)
     files available.
  - They are meant to be played with. They are for exploration
     and experimentation as well as to illustrate how to write WinSock
     applications.

The icons used for each sample don't mean much, but they meet
the following three criteria:

    - They each contain the socket from the official WinSock icon.
    - Each one is colorful in its own unique and wonderful way.
    - Each took under 10 minutes to create.

