VI. File Transfer

1. FTP (File Transfer Protocol) permits copying files from one 		
internet host to another.
Downloading: Copying files from the remote computer to yours
Uploading: Copying files from your computer to the remote 
	computer

2. Requirement: You need accounts (with passwords) on both the local host 
and the remote host.
There is a special account (anonymous, E-mail address as password) 
that users can access while unregistered for certain internet hosts that are 
set up to offer this service.

3. Benefits of Anonymous FTP:
* Huge Number (Thousands) of Sites for downloading files
* Largest distributed library of information ever accumulated
* Library that is always growing, never closes, covers myriad
 	topics
* All this is Free
* A principal way of distributing software on the internet
* Used to archive and disseminate technical information that
 	defines the Internet (rfc* files)

5. Some FTP Command meanings:
quit				Close connection to the remote 							host, stop the ftp program
? or help			Display a list of all ftp commands
? <ftp command>		Display a one-line summary of 							the specified command
help <ftp command> 
!				Local host: pause ftp and start a 							shell
! <Unix Command>		Local host: pause ftp and execute 							that Unix command

Connecting:
open <hostname>		Establish connection to the 							specified computer
close			Close the connection to the remote 							host, stay in the ftp program
user [name [password] ]	set user name for ftp session

Directories:
cd <directory>			Remote host: change to the 							specified directory
cdup				Remote host: change to the parent 							directory
dir [directory [file] ]	Remote host: display a long directory 							listing
lcd [directory]		Local host: change directory
ls [directory [file] ]	Remote host: display a short directory 							listing
pwd			Remote host: display the current 							directory name

Transferring Files:
get [remotefile [localfile] ]	Download one file from remote 							host, no wildcards
mget [remotefiles ]		Download multiple files from remote 							host, wildcards ok
put [localfile [remotefile] ]	Upload one file from remote 							host, no wildcards
mput [localfiles ]		Upload multiple files from remote 							host, wildcards ok

Setting Options:
ascii				Set file type to ASCII text file 
						(default)
binary				Set file type to binary file (do this 
						if not sure)
hash				Yes/No: show # for each data 
						block transferred
prompt				Yes/No: prompt for multiple file 
							transfers
status				Display current status of options

6. Notes about ftp commands
* To stop an ftp command as it is executing, press <CTRL-C>

* To run a UNIX command while under ftp control, type !command or
	! to get multiple commands

* To display text files to the terminal (rather than download into a file)
	ftp> get readme.txt -

* Browse any size text files within ftp (a screenful at a time)
	ftp> get readme.txt |more

* Browse a directory within ftp (a screenful at a time)
	ftp> get . |more

* Different File types: Suffix file.Z	Compressed file (use $ 								uncompress file.Z)
			Suffix file.tar	Archive file (use $ tar 							-xvf file.tar to extract)
					use $ tar -tvf file.tar 
					to view contents)
			Suffix file.txt	text file
			README		General information about 							this directory
			index		A description of each file in 							the directory
			ls-lR.Z		A file having a long list, 							sorted alphabetically
			ls-ltR.Z	A file having a long list, 							sorted by latest file first

* It is possible to create a Unix Script that calls ftp and 	
downloads based on a data file of ftp commands.  Such a 	
script can run unattended and can be prescheduled using the at command

7. Requesting (Anonymous) ftp by mail (64000 bytes at a time)
* Use a program called ftpmail to mail a request to an ftpmail server.
$ mail ftpmail.decwrl.dec.com	#in California 
					[16.1.0.1]; or
$ mail bitftp@pucc.princeton.edu	#via bitnet 
					[128.112.129.99]
Subject: Requesting a text file
reply arkay@hcc-cis.ctc.edu
connect cathouse.org <username> <password> <account>
ascii
chdir /misc/fun/humor/british.humour/monty.python/flying.circus
get argument.clinic
quit
<Ctrl-D>
EOT
	
* Selected Commands
	
Specifying your E-mail address:
	reply <E-mail Address>		mail response

Connect to the Host:
	connect <host>			Connect to specified
 						Anonymous FTP host

Setting options:
	ascii				Files to be mailed are text
 							files
	binary				Files to be mailed are
 						non-text or text
 							files
	uuencode			convert binary files to
 						text using uuencode
	btoa				convert binary files to text
 						using btoa

Specifying the directory:
	chdir <directory>		Change to the 
						indicated directory
	
Requesting Files:
	get <file>		Download file (up to 10
 						gets per ftpmail
 							message)

Requesting Information:
	help				Send and describe 
						how to use ftpmail
	dir [ directory ]		Send a long directory
 						listing
	ls [ directory ]		Send a short directory
 						listing

Ending the Session:
	quit				Terminate the session,
						ignore the rest
						of message.

Questions? Robert Katz: katz@ned.highline.edu
Last Update December 7, 1999