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- Using "anonymous ftp"
- ---------------------
-
- Using "anonymous ftp" to get files from other Internet machines
-
- Mark Moraes, University of Toronto
-
- Anonymous ftp is a facility offered by many machines on the Internet.
- This permits you to log in with the ftp program with the user name
- 'anonymous' or the user name 'ftp'. When prompted for a password, type
- your e-mail address -- it's not necessary, but it's a courtesy for
- those sites that like to know who is making use of their facility. Be
- courteous.
-
- Most ftp sites do not like people getting files from them during their
- working hours since they usually have other load on their systems --
- avoid 9am-5pm in their time-zone.
-
- Also bear in mind that countries are often connected by relatively
- low-bandwidth links, so please check local archive sites before you
- connect to some distant country to fetch something. If you think the
- item you want is popular, ask your local archive site sysadmin, who
- may be willing to set up a copy on the local archive.
-
- Different archive sites have different forms of etiquette -- if you see
- a README or README.TXT file in the ftp directory, please read it.
-
- Once you're connected to the remote site via ftp, you can look around
- and retrieve files. (Most anonymous ftp sites do not permit people to
- store files) The ftp program prompts you with
-
- ftp>
-
- and offers a few commands that are similar to Unix. "cd" changes your
- directory on the remote machine, "lcd" changes your directory on the
- local machine, "get" will get a file, etc. See the manual page for ftp
- (use the command "man ftp")
-
- Typically, a directory called 'pub' is where the interesting things
- are stored. Some sites will have a file with a name like ls-lR, that
- contains a complete list of the files on that site. Otherwise, you can
- type ls -lR and get such a listing -- for some sites, this can take
- a LONG time. This doesn't work on some sites.
-
- Usually, files are grouped in composite "archive" files, so you don't
- have to get many small files separately. The most common Unix archive
- file format for the Internet is tar, usually indicated by a ".tar"
- suffix in the file name. tar archives can be unpacked by running the tar
- command -- you may want to first do a 'tar t' on the file to see what
- it contains before unpacking it.
-
- Occasionally, people use shell archives (with .shar or .sh suffixes)
- instead. These are Unix Bourne shell scripts, with files encapsulated
- in them. Be careful when unpacking shell archives since they have to
- be run through the Bourne shell to unpack them. The simplest way is
- to use the unshar command, if your system has one installed.
- Otherwise, you have to delete all the leading text with an editor and
- then run the rest of the text through "sh" o unpack the archive. Make
- sure you're in the directory you want the files in before you try
- unpacking the archive, since there's no good way to list the contents
- of an archive.
-
- Files are often stored compressed -- for Unix, the most common form
- is the compress program, indicated by a .Z suffix on the file name.
-
- Sometimes, people use programs like arc (indicated by a .ARC suffix),
- zoo (.ZOO), zip (.ZIP) or lharc (.LZH), which are combined archival
- and compression formats. (There are lots of other archive formats -
- talk to the systems staff if you encounter them and don't know how to
- deal with them) Macintosh archives are often in StuffIt format (.SIT).
- In each case, you need the relevant extraction program. Usually, the
- archive site will also have a copy of the extraction program for ftp.
- Finally, there's the "self-extracting" archive format, popular in the
- PC world -- they look like executable programs (.EXE) and when run,
- they unpack the files they contain.
-
- When retrieving non-text files, you must use binary mode, otherwise
- the file gets messed up. To do this, use the 'binary' command. (It's
- safe to set this for text files if the other end is a Unix system,
- since Unix doesn't differentiate between text and binary file
- representation. If the site at the other end is non-Unix, you may need
- to use some other mode -- see the documents for that site and for ftp)
-
- An example session follows -- the commands I typed are all underlined
- with a row of carets (^^^^) and are usually typed at the % or ftp>
- prompt.
-
- % ftp ftp.cs.toronto.edu
- ^^^^^^^^^^^^^^^^^^^^^^
- Connected to ftp.cs.toronto.edu.
- 220 neat.cs FTP server (Version 5.55 Tue Aug 8 22:48:27 EDT 1989) ready.
- Name (ftp.cs.toronto.edu:moraes): anonymous
- ^^^^^^^^^
- 331 Guest login ok, send ident as password.
- Password:moraes@cs.toronto.edu
- ^^^^^^^^^^^^^^^^^^^^^
- 230 Guest login ok, access restrictions apply.
- Remote system type is UNIX.
- ftp> dir
- ^^^
- 200 PORT command successful.
- 150 Opening ASCII mode data connection for /bin/ls.
- total 62
- drwxr-xr-x 2 0 0 512 Nov 20 1988 bin
- drwxr-xr-x 11 0 0 2048 Dec 29 00:45 pub
- 226 Transfer complete.
- ftp> cd pub
- ^^^^^^
- 250 CWD command successful.
- ftp> dir
- ^^^
- 200 PORT command successful.
- 150 Opening ASCII mode data connection for /bin/ls.
- total 4523
- ...
- -rw-r--r-- 1 0 0 51251 Sep 16 12:02 ssl.tar.Z
- ...
- 226 Transfer complete.
- ftp> hash
- ^^^^
- Hash mark printing on (1024 bytes/hash mark).
- ftp> binary
- ^^^^^^
- 200 Type set to I.
- ftp> get ssl.tar.Z
- ^^^^^^^^^^^^^
- 200 PORT command successful.
- 150 Opening BINARY mode data connection for ssl.tar.Z (51251 bytes).
- ##################################################
- 226 Transfer complete.
- 51251 bytes received in 0.94 seconds (53 Kbytes/s)
- ftp> quit
- ^^^^
- 221 Goodbye.
-
- Now, to see what ssl.tar.Z contains, I can use:
-
- % uncompress < ssl.tar.Z | tar tvf -
- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
- drwxrwxr-x 7/0 0 Sep 16 11:58 1989 ssl/
- -rw-r--r-- 7/0 301 Sep 16 11:58 1989 ssl/Makefile
- -rw-r--r-- 7/0 240 Jun 2 01:08 1988 ssl/README
- -rw-r--r-- 7/0 20642 Feb 26 21:43 1988 ssl/file.ssl
- -rw-r--r-- 7/0 5241 Feb 21 15:25 1988 ssl/file.sst
- -rw-r--r-- 7/0 56581 Sep 16 11:57 1989 ssl/ssl.c
- -rw-r--r-- 7/0 20642 Feb 26 20:08 1988 ssl/ssl.ssl
- -rw-r--r-- 7/0 5241 Feb 26 21:41 1988 ssl/ssl:sst.c
- -rw-r--r-- 7/0 5395 Feb 26 21:41 1988 ssl/ssl:sst.h
- -rw-r--r-- 7/0 12211 Mar 30 22:34 1988 ssl/sslskel.c
- -rw-r--r-- 7/0 274 Feb 26 20:42 1988 ssl/sslskel.ssl
- -rw-r--r-- 7/0 55 Feb 26 20:42 1988 ssl/sslskel.sst.c
- -rw-r--r-- 7/0 1001 Feb 26 20:42 1988 ssl/sslskel.sst.h
-
- To extract the files, I use
-
- % uncompress < ssl.tar.Z | tar xvf -
- ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
- ssl/
- ssl/Makefile
- ssl/README
- ssl/file.ssl
- ssl/file.sst
- ssl/ssl.c
- ssl/ssl.ssl
- ssl/ssl:sst.c
- ssl/ssl:sst.h
- ssl/sslskel.c
- ssl/sslskel.ssl
- ssl/sslskel.sst.c
- ssl/sslskel.sst.h
-
- ---