Roadmap96: MAP05 - LISTSERV
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MAP05: LISTSERVs
"I have made this letter longer than usual,
only because I have not had the time to make it shorter."
-- Blaise Pascal, Provincial Letters
In MAP02, I showed you how to use the LISTSERV file server to retrieve archived files. Today, I am going to show you some new things about LISTSERV, including what LISTSERV was originally designed for: mailing lists like the one that distributed this letter to you.
Remember, though, that today's lesson covers only LISTSERV lists. In fact, this lesson is an elementary lesson for ordinary LISTSERV users like you and me. Tomorrow's lesson will be a highly technical lesson for LISTSERV (and other mailing list server) gurus-to-be.
What is a LISTSERV mailing list? Quite simply, it is an e-mail-based mailing list for a whole bunch of people who share similar interests. This list is maintained by a LISTSERV program. Anyone can subscribe to a LISTSERV mailing list by sending a SUBSCRIBE command (remember that one?) to the LISTSERV administrative address.
Any e-mail letter sent to the list's address is copied and mass-mailed to the e-mail box of every person subscribed to the list. Everyone else on the list can then reply to that letter, and then ... well, you get the picture. LISTSERV lists give you a way to have open discussions with dozens or even hundreds of people on a myriad of topics. Best of all, it is all done through e-mail!
I want to say something about the difference between list addresses and LISTSERV administrative addresses. Let's pretend that I create a list at the InterNIC for the open discussion of power-line-chomping squirrels. I will even call the list "SQUIRREL."
The address for our pretend squirrel discussion list would be [email protected] Any e-mail letter sent to the [email protected] address would be copied and mass-mailed to every single person subscribed to the squirrel list. That's simple enough.
But how are people going to subscribe to my squirrel list? We need a second address just to handle all of the commands for my list (and for other lists as well)! That second address is the LISTSERV administrative address which, in this case, is [email protected]
Are you starting to see the picture?
The list address is where you send a message if you want it to be distributed to everyone else subscribed to that list. The LISTSERV administrative address is where you send all of your commands.
What would happen if you sent a command (like SUBSCRIBE or GET) to the discussion list's address instead of to the LISTSERV administrative address? Simple: your command would be treated as a letter and would be sent to everyone on the list (how embarrassing!).
Also, never send chatty text to the LISTSERV administrative address. For example, sending an e-mail letter to the LISTSERV administrative address that says, "Hi, I am really interested in your list -- please subscribe me" would only generate a really weird-looking error message. LISTSERV is a computer program, not a person, and only understands specific commands.
Remember this (and you will see this on a pop quiz some time):
- Send your LETTERS to the list address!
- Send your COMMANDS to the LISTSERV administrative address!
Now, life would be a whole bunch easier if the only LISTSERV in the world was at the InterNIC. But, it isn't. There are thousands of different LISTSERVs around the world, and there are literally tens of thousands of different LISTSERV lists.
How are you ever going to find out what different discussion lists are out there, and what these lists' addresses are? Well, there are a few ways to do this:
- Word of mouth -- someone tells you about a hot new list you need to check out.
- Internet Yellow Pages -- there are some GREAT books you can buy in most bookstores that tell you where lots of the neat stuff is on the Internet.
- The LIST GLOBAL or LISTS GLOBAL /STRING command -- we'll talk about this tomorrow.
- Announcements on other lists.
How are you ever going to figure out which LISTSERV administrative address goes with which discussion list? EASY! This trick only works with LISTSERV discussion lists, but if you take the full address of a discussion list (like [email protected]) and replace the discussion list's name with the word "LISTSERV," you'll end up with the correct LISTSERV administrative address for that particular list. In this case, the correct LISTSERV administrative address for the squirrel list would be [email protected]
A few more examples:
List address Administrative address
[email protected] [email protected]
[email protected] [email protected]
[email protected] [email protected]
[email protected] [email protected]
Why is this important to know? Well, let's say that I tell you that there is a LISTSERV list called [email protected] to which you should subscribe. All I have given you is the list's address. Remember, you can only send LETTERS to the list address. You need to know the LISTSERV administrative address in order to subscribe!
With this trick, you automatically know that the LISTSERV administrative address for [email protected] is [email protected] and you can subscribe to the list without any problem!
You may notice that some list addresses look something like this:
CRUISE-L@UNLVM
NAVIGATE@UBVM
Those are BITNET addresses. BITNET is an old, non-Internet network that used to connect many major colleges and universities. To turn BITNET addresses into something that you can use, you will have to add .BITNET to the end of the addresses:
and the LISTSERV administrative addresses would be:
One nice thing about this is that you can almost always tell that a list is a LISTSERV list by looking at the list's address. If the address is LIST@NODE or [email protected], you can all but bet that the list is a LISTSERV list.
Some of you may be at sites that do not allow mail to BITNET addresses. You can bypass this restriction by taking the address
dropping the .BITNET, so the address becomes
LIST@NODE
changing the @ to a %, so the address becomes
LIST%NODE
and then adding @CUNYVM.CUNY.EDU to the end, so that the final address becomes
LIST%[email protected]
This is called the "percent hack," and it works because CUNY.EDU is one of many gateways between the Internet and BITNET.
Now let's talk about some new LISTSERV commands. You already know the SUBSCRIBE command
SUBSCRIBE listname yourfirstname yourlastname
and the GET command
GET filename filetype F=MAIL
I want to show you a couple of other commands that will make your life a whole lot easier (remember, all commands must be sent to a LISTSERV administrative address).
If you ever need to unsubscribe from a list, the SIGNOFF command will take care of everything. There are three different SIGNOFF commands that you can use:
SIGNOFF listname to unsubscribe from a particular list
(you need to replace the word
"listname" with the name of the list
you are dropping)
SIGNOFF * to unsubscribe from every list at a
particular LISTSERV address
SIGNOFF * (NETWIDE to unsubscribe from every LISTSERV list
on the planet
Have you ever accidentally thrown away an e-mail letter? Well, if that letter was from a LISTSERV list and if that list keeps an archive, you can retrieve that letter from the LISTSERV! Here is how to do it:
- Send an INDEX listname F=MAIL command to the LISTSERV administrative address (for example, to get the index for the SQUIRREL list, your command would say INDEX SQUIRREL F=MAIL).
- Look through the index to find the file or notebook that you want to retrieve (the index will even tell you the filename and filetypes for each of the files!).
- Use the GET filename filetype F=MAIL command to get the file or notebook that you want.
Remember: you send LETTERS to the list address; you send COMMANDS to the LISTSERV administrative address. Etch this into your brain. :)
There are a couple more things I want to talk about, but I will save them for tomorrow. :)
HOMEWORK:
This homework assignment is completely optional. Also, you are reminded to contact your local Internet Service Provider if you have questions about, or difficulties with, any part of the Roadmap workshop (please do not write me -- my mailer cannot handle the volume). Finally, please remember that replying to this letter with your GET commands will *NOT* work. You *MUST* write a new letter to the LISTSERV administrative address for your GET commands to work.
ASSIGNMENT: If you would like a very brief guide to LISTSERV, GET the file LISTSERV REFCARD from the LISTSERV file server at the InterNIC. This is a list of a whole bunch of LISTSERV commands, along with a brief explanation of what each command does.
Start Lesson Six | Go to the Roadmap96 Syllabus | Go to the Roadmap96 Homepage
Originally written by Patrick Douglas Crispen
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