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Unit 13: FTP Server

dir List the files in the current directory on the remote computer. notes
ls Same as ‘dir’, but shows less information sometimes.
get Copy a file from the remote computer to yours
hash Puts a ‘#’ on the screen for every <number> of bytes transferred. <number>
is 1024 in some cases, 2048 in others but is between 1024 and 4096 in most
cases.
Check the ftp ‘help’ function for more info on the number for your
clientprogram.
help Gives help on the use of commands within the ftp program
lcd Change the directory on your computer (the ‘l’ is for local)
lpwd Shows the present working directory (pwd) on your computer (the ‘l’ is
for local). Note: this may not work on all machines. On a Unix machine,
try !pwd if lwpd doesn’t work.
mget Copy multiple files from the remote computer to yours

pwd Shows the present working directory (pwd) on the remote computer

Task “Using FTP Clients to test anonymous read access.” Comment

procedure

Anonymous FTP is a facility offered by many machines on the Internet. This permits you to log
in 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. Some sites require a valid e-mail address, others
don’t.
You can then look around and retrieve files. (Most anonymous ftp sites do not permit people to
store files). Note that when you retrieve files, you have to know where the files are going to end
up on your machine. This is where the ‘lpwd’ command comes in handy. Also note that when
you have transferred a file that you want to use on your PC, but you run ftp from a Unix machine
(or a similar mainframe or network machine), you will have to ftp the file from the Unix machine
to your PC first (this is assuming that you can’t ftp to outside your company or campus from
your PC, otherwise you could have gotten the file directly to the PC).
This may sound silly, but sometimes people don’t know where their files are stored or a system
administrator decides to give ftp access to only a few systems.
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 (the size of the
resulting file can be anywhere between approximately 2000 bytes and 25Mb).
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, but the result might look a bit
different from an ASCII transfer)
If the site at the other end is non-Unix, you may need to use some other mode -- see the documents
or README files for that site and for FTP (common other modes, are LZ for VAX Multinet
servers, tenex or image for some others).

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