                         User Mode +g Documentation

Hybrid 7 includes a new and power feature that all users can take advantage
of to help prevent flooding and unwanted messages.  This new feature is 
invoked by setting user mode +g.  When a client is set +g, that user will
be in "Caller ID" mode.  Any user that messages a +g client will receive
a notice saying that they are in +g (server side ignore) mode.  The target
client (who is set +g) will also receive a notice saying that so and so
messaged them, and that they are in +g mode.

The target of the message will only receive one notification per minute, from
any client, in order to help prevent flooding.  The sender will NOT have the
rate limit, and will receive a notice saying the target is in +g mode every
time they send a message.  Note that this behavior is similar to the way AWAY
messages are done.

There are numerous benefits for both opers and regular users, including the
ability to stop spambot messages from ever reaching your client, stopping
private message and CTCP floods, and being able to sit on IRC in privacy.

One question that arises is how to message specific users, while blocking
out everyone else.  The command ACCEPT is your answer.  To add a user to
your accept list, issue the raw command ACCEPT <nick>,<nick>,<nick>,...

You will not receive a reply from the ACCEPT command if it is succesful,
only if an error has occured.  There are three possible errors, shown by
numerics:

   ERR_ACCEPTFULL (456): :irc.server 456 client :Accept list is full
     - This is sent when an accept list is full.
   ERR_ACCEPTEXIST (457): :irc.server 457 client target :already exists
     - This is sent when a client tries to add a user to the accept list
       that already exists there
   ERR_ACCEPTNOT (458): :irc.server 458 client target :doesn't exist
     - This is sent when a client tries to remove a user from their accept
       list who is not on the accept list.

That user will now be able to send messages to your client until the
association is broken.

Associations break in one of the following situations:  when an accepted user
QUIT's (or is on the other side of a split), you QUIT, or the accepted user
changes their nick.  The reason why a remote user's nick change will remove
them from your accept list is so that you cannot track a user after they
changed their nick.

Viewing the accept list is also very easy.  Issue the raw command ACCEPT *.
Removing a user from your accept list is also simple.  Issue the command
ACCEPT -<nick>.  

                              Sample Session

The easiest way to see how this works is by experiencing it.  Seeing a sample
session can help understand what goes on though.

Client Hwy-LL is set +g initially.
Client Hwy101 wants to message Hwy-LL

Note that some clients may have to use /quote ACCEPT instead of /accept.

--

Client Hwy101:  /msg Hwy-LL hi
Hwy101 will see:  -Hwy-LL- *** I'm in +g mode (server side ignore).
                  -Hwy-LL- *** I've been informed you messaged me.

Hwy-LL will see:  Client Hwy101 [wcampbel@admin.irc.monkie.org] is messaging
                    you and you are +g

The sender will receive the NOTICE from the target of the message, while
the recipient will receive the NOTICE from the server.

--

If Hwy101 sends another message to Hwy-LL (before the minute expires), he will
see:  -Hwy-LL- *** I'm in +g mode (server side ignore).
and will not receive the second notice

Hwy-LL will NOT see any notice.

--

Hwy-LL now wishes to see messages from Hwy101 and SpamBot

Client Hwy-LL:  /accept Hwy101,SpamBot

Neither side will be told of the change in the accept list, Hwy-LL should
presume that the accept was succesful if no error occurs.

Now Hwy-LL can see messages from Hwy101 and SpamBot without any blockage.
If Hwy101 was also set +g, then he would have to issue /accept Hwy-LL
before he would be able to see messages from Hwy-LL.

--

Hwy-LL now wants to see who is on his accept list.

Client Hwy-LL:  /accept *

Hwy-LL will see:
  irc.server 281 Hwy-LL Hwy101 SpamBot
  irc.server 282 Hwy-LL :End of /ACCEPT list

The replies are in numeric form to help parsing by scripts.
--

Hwy-LL realises he added a spambot to his list, and wants to remove it, and
allow messages from services

Client Hwy-LL:  /accept -SpamBot,services

Hwy-LL will now only accept messages from Hwy101 and services.

--

The nicks to be added can be in ANY order, however you cannot add or remove
AND list.  
    /ACCEPT x,y,-z,f,-a would be acceptable.
    /ACCEPT x,y,-z,* would ignore the * and generate an invalid nick
                     response.

Like Dalnet and Undernet's SILENCE system, the accept list only exists while
you are connected to IRC.  In order for you to have the same accept list
every time you come onto IRC, you must put the accept commands into your 
client's auto-perform, or manually issue the commands each time.  

This system may seem similar to the SILENCE system, but it is actually a
reverse SILENCE.  SILENCE ignores certain users and allows the rest.  Mode
+g ignores all users except certain ones (on your accept list.)  Both systems
have their place, but the mode +g in Hybrid 7 is what the developers thought
would be most useful for clients.

The goals of this user mode is to provide protection from flooding and
spamming, and to provide users with a means to keep their privacy.

We hope that these goals are obtained.

--
W. Campbell
$Id: modeg.txt,v 1.2 2003/08/14 07:51:10 stu Exp $
