Big Dummy's Guide To The Internet - Electronic Frontier Foundation (reading rainbow books .txt) 📗

in bytes. If the line is for a directory, the

number gives you a rough indication of how many items are in that

directory — a directory listing of 512 bytes is relatively small. Next

comes the date the file or directory was uploaded, followed (finally!) by

its name.

Notice the README.POSTING file up at the top of the directory. Most

archive sites have a “read me” document, which usually contains some

basic information about the site, its resources and how to use them.

Let’s get this file, both for the information in it and to see how to

transfer files from there to here. At the ftp> prompt, type

get README

and hit enter. Note that ftp sites are no different from Unix sites in

general: they are case-sensitive. You’ll see something like this:

200 PORT command successful.

150 Opening BINARY mode data connection for README (4444 bytes).

226 Transfer complete. 4444 bytes received in 1.177seconds (3.8 Kbytes/s)

And that’s it! The file is now located in your home directory on your host

system, from which you can now download it to your own computer. The

simple “get” command is the key to transferring a file from an archive

site to your host system.

If you want to download more than one file at a time (say a series

of documents, use mget instead of get; for example:

mget *.txt

This will transfer copies of every file ending with .txt in the given

directory. Before each file is copied, you’ll be asked if you’re sure

you want it. Despite this, mget could still save you considerable

time — you won’t have to type in every single file name. If you want to

save even more time, and are sure you really want ALL of the given files,

type

prompt

before you do the mget command. This will turn off the prompt, and all

the files will be zapped right into your home directory.

There is one other command to keep in mind. If you want to get a

copy of a computer program, type

bin

and hit enter. This tells the ftp site and your host site that you are

sending a binary file, i.e., a program. Most ftp sites now use binary

format as a default, but it’s a good idea to do this in case you’ve

connected to one of the few that doesn’t.

To switch to a directory, type

cd directory-name

(substituting the name of the directory you want to access) and hit

enter. Type

ls

and hit enter to get the file listing for that particular directory.

To move back up the directory tree, type

cd ..

(note the space between the d and the first period) and hit enter. Or

you could type

cdup

and hit enter. Keep doing this until you get to the directory of

interest. Alternately, if you already know the directory path of the

file you want (from our friend archie), after you connect, you could

simply type

get directory/subdirectory/filename

On many sites, files meant for public consumption are in the pub

or public directory; sometimes you’ll see an info directory.

Almost every site has a bin directory, which at first glance

sounds like a bin in which interesting stuff might be dumped. But it

actually stands for “binary” and is simply a place for the system

administrator to store the programs that run the ftp system. Lost+found

is another directory that looks interesting but actually never has

anything of public interest in them.

Before, you saw how to use archie. From our example, you can see

that some system administrators go a little berserk when naming files.

Fortunately, there’s a way for you to rename the file as it’s being

transferred. Using our archie example, you’d type

get zterm-sys7-color-icons.hqx zterm.hqx

and hit enter. Instead of having to deal constantly with a file called

zterm-sys7-color-icons.hqx, you’ll now have one called, simply,

zterm.hqx.

Those last three letters bring up something else: Many program files

are compressed to save on space and transmission time. In order to

actually use them, you’ll have to use an un-compress program on them first.

7.4 ODD LETTERS — DECODING FILE ENDINGS

There are a wide variety of compression methods in use. You can

tell which method was used by the last one to three letters at the end of

a file. Here are some of the more common ones and what you’ll need to un-

compress the files they create (most of these decompression programs can

be located through archie).

.txt or .TXT By itself, this means the file is a document, rather than a

program.

.ps or .PS A PostScript document (in Adobe’s page description

language). You can print this file on any PostScript

capable printer, or use a previewer, like GNU project’s

GhostScript.

.doc or .DOC Another common “extension” for documents. No decompression

is needed, unless it is followed by:

.Z This indicates a Unix compression method. To uncompress,

type

uncompress filename.Z

and hit enter at your host system’s command line. If the

file is a compressed text file, you can read it online by

instead typing

zcat filename.txt.Z |more

u16.zip is an MS-DOS program that will let you download

such a file and uncompress it on your own computer. The

Macintosh equivalent program is called MacCompress (use

archie to find these).

.zip or .ZIP These indicate the file has been compressed with a common

MS-DOS compression program, known as PKZIP (use archie to

find PKZIP204.EXE). Many Unix systems will let you un-ZIP

a file with a program called, well, unzip.

.gz A Unix version of ZIP. To uncompress, type

gunzip filename.gz

at your host system’s command line.

.zoo or .ZOO A Unix and MS-DOS compression format. Use a program called

zoo to uncompress

.Hqx or .hqx Mactintosh compression format. Requires the BinHex program.

.shar or Another Unix format. Use unshar to uncompress.

.Shar

.tar Another Unix format, often used to compress several related

files into one large file. Most Unix systems will have a

program called tar for “un-tarring” such files. Often, a

“tarred” file will also be compressed with the gz method,

so you first have to use uncompress and then tar.

.sit or .Sit A Mactinosh format that requires the StuffIt program.

.ARC Another MS-DOS format, which requires the use of the ARC

or ARCE programs.

.LHZ Another MS-DOS format; requires the use of LHARC.

A few last words of caution: Check the size of a file before you get

it. The Net moves data at phenomenal rates of speed. But that 500,000-

byte file that gets transferred to your host system in a few seconds

could take more than an hour or two to download to your computer if

you’re using a 2400-baud modem. Your host system may also have limits on

the amount of bytes you can store online at any one time. Also, although

it is really extremely unlikely you will ever get a file infected with a

virus, if you plan to do much downloading over the Net, you’d be wise to

invest in a good anti-viral program, just in case.

7.5 THE KEYBOARD CABAL

System administrators are like everybody else — they try to make

things easier for themselves. And when you sit in front of a keyboard

all day, that can mean trying everything possible to reduce the number

of keys you actually have to hit each day.

Unfortunately, that can make it difficult for the rest of us.

You’ve already read about bin and lost+found directories. Etc is

another seemingly interesting directory that turns out to be another

place to store files used by the ftp site itself. Again, nothing of any

real interest.

Then, once you get into the actual file libraries, you’ll find that

in many cases, files will have such non-descriptive names as V1.1-

AK.TXT. The best known example is probably a set of several hundred

files known as RFCs, which provide the basic technical and

organizational information on which much of the Internet is built.

These files can be found on many ftp sites, but always in a form such as

RFC101.TXT, RFC102.TXT and so on, with no clue whatsoever as to what

information they contain.

Fortunately, almost all ftp sites have a “Rosetta Stone” to help

you decipher these names. Most will have a file named README (or some

variant) that gives basic information about the system. Then, most

directories will either have a similar README file or will have an index

that does give brief descriptions of each file. These are usually the

first file in a directory and often are in the form 00INDEX.TXT. Use

the ftp command to get this file. You can then scan it online or

download it to see which files you might be interested in.

Another file you will frequently see is called ls-lR.Z. This contains

a listing of every file on the system, but without any descriptions (the

name comes from the Unix command ls -lR, which gives you a listing of all

the files in all your directories). The Z at the end means the file has

been compressed, which means you will have to use a Unix un-compress command

before you can read the file.

And finally, we have those system administrators who almost seem to

delight in making things difficult — the ones who take full advantage of

Unix’s ability to create absurdly long file names. On some FTP sites, you

will see file names as long as 80 characters or so, full of capital letters,

underscores and every other orthographic device that will make it almost

impossible for you to type the file name correctly when you try to get it.

Your secret weapon here is the mget command. Just type mget, a space, and

the first five or six letters of the file name, followed by an asterisk, for

example:

mget This_underscore_F*

The FTP site will ask you if you want to get the file that begins with that

name. If there are several files that start that way, you might have to

answer ‘n’ a few times, but it’s still easier than trying to recreate a

ludicrously long file name.

7.6 SOME INTERESTING FTP SITES

What follows is a list of some interesting ftp sites, arranged by

category. With hundreds of ftp sites now on the Net, however, this list

barely scratches the surface of what is available. Liberal use of archie

will help you find specific files.

The times listed for each site are in Eastern time and represent

the periods during which it is considered acceptable to connect.

AMIGA

ftp.uu.net Has Amiga programs in the systems/amiga directory.