Instances - Class Message

Class message is special. When someone talks about a Zephyr instance they probably mean an instance of class message. Just like other classes, it is possible to subscribe to all of the instances of class message (many people do). This means that zephyr instances are very public and are not a good place to discuss anything you do not want made public..

To subscribe to the particular instance help, you would type

zctl sub message help \*

In any of these examples, you can also use zctl add. This would give you a permanent subscription, in this case to the instance help. A permanent subscription to the instance help would show in your .zephyr.subs file as the line message,help,*

Looking at the above example of a subscription to instance help, the * in the recipient field indicates a broadcast message. (You need to type a \ before the * so that it is interpreted correctly by the shell.) In other words, the * means that means that you are receiving zephyrgrams that have been sent to everyone who subscribes to that instance. The other option for recipient in a Zephyr subscription is %me%, which indicates that you are subscribed to zephyrgrams sent specifically to you. This is generally not useful on an instance such as help, which is intended to send messages to a large number of people, rather than a specific user. The help instance is used by people who want to ask a question, about anything ranging from using Athena, to progamming, to random facts about MIT, Boston, history, etc. If you just want to ask a question, you probably want to use zctl sub to ask it and see the answer, since there are a lot of zephyrgrams on this instance, and you may not want them distracting you when you don't have a question to ask. Many knowledgeable people are subscribed to the instance help.

Public instances are not limited to the instances people often write to. Any public instance (i.e. on the class message) that someone chooses to write to exists when they decide to write to it. Obviously, you can't explicitly subscribe to each one of these, but you can explicity subscribe to instances that you know of. Some others besides help are white-magic, which is an instance for random chatting, b5, which is an instance where people chat about Babylon 5, and instances like 6.170, where people talk about that particular subject.

You can also subscribe to every possible public instance by typing zctl sub message \* \*. In this case, the * for the instance name acts as a wildcard which subscribes you to all instances in the class message. The * wildcard for instances is the reason that instances on class message are called public--anyone who chooses to subscribe to message \* \* will get zephyrgrams sent to any instance you might send to, so there is no way to keep people from finding out about the instance and jumping into a conversation on it. There are actually a number of people who are always subscribed to ``star star,'' as it is often called.

If you do want to subscribe to message \* \*, there are a few useful things you might want to know. First of all, a word of warning: you will receive a lot of zephyrgrams, which can be very confusing if you do not customize your dotfiles to make zephyrgrams on instances look different from personal zephyrgrams, and change where they appear on your screen. It is also rather distracting. To decrease the volume of zephyrgrams somewhat, you can filter out zephyrgrams on certain instances that you have no interest in reading by creating ``negative subscriptions'' in your .Zephyr.subs file. For each instance you want to filter out, you would add a line reading -message,silly-instance,* (where silly-instance is the name of the instance you want to filter out). You would then be subscribed to all public instances except those listed with a minus sign in your .zephyr.subs file. Also, there is a command called zpunt in the sipb locker which you can use to unsubscribe from a particular instance temporarily. The zpunt command is necessary for people who are subscribed to ``star star'' because using the zctl unsub command will not work in this case. It works in the same way that the ``negative subscriptions'' in your .zephyr.subs file do. To use zpunt, you would type

add sipb; zpunt annoying_instance

If you want to resubscribe to that instance before you log out, you can type

zunpunt annoying_instance

Geoffrey G Thomas 2009-02-09