irc2.10's new !channels
A user-friendly explanation by Kaspar
Slightly completed by Mario
The following explanation assumes that you are at least a bit
familiar with the Internet Relay Chat (IRC) and that terms like
"channels", "nicks", "servers" and "clients" are known to you.
The new IRC server version irc2.10 (mainly used on IRCNet
) introduces a new type of
channels to IRC: unique, uncollidable channels marked "!channels".
To explain what exactly that means, let us examine the situation on
IRC before irc2.10 became reality:
As you know, a channel does only exist when at least one person is
on it. And as you know too, an existing channel is known on all servers
connected to a specific net, which means that you can join that channel
on every connected server of a net and you will see there the same
user(s) (if the channel had existed before your join of course). But
what happened when some server split temporarily away from the net
(ie. that for a certain amount of time, the server is not connected
to the other servers anymore)?
Well, roughly, this is what happened on the server which splitted away
and was then alone: All channels on it were "destroyed" (they became
nonexistent) except those on which was at least one user who was on
the server which split away. Respectively the same happened on the other
side of the net (where the rest of the servers were). But if, before the
split, there were users on the same channel coming from both sides
(ie. partly from the server that will split away and partly from the
other side), then, after the split, you had two channels with exactly
the same name but with different users (and maybe different modes) on
both sides. Keeping this situation in mind, here's what happened when
both sides of the net (until then separated) reconnected to each other,
forming again a single, non-separated IRC net:
Since you had different states for the same channel on both sides, the
state of the concerned channel had to be "resynchronized", ie. that on
both sides had to be created the same state of the channel (same users,
same modes). This was done by the concerned servers. What you usually
saw then was one server opping other users ("server-ops") or setting
other modes ("server-modes"). This also usually happens on so called
"channel takeovers", which you probably have already encountered on IRC.
Those "channel takeovers" were an obvious problem of the former
channel design, since channels were collidable in the way described
above. Thus was the situation in the past, before the IRC server
version irc2.10 became reality. Now, let's examine how things look
like with the new server version.
A new channel type
The latest IRC server version irc2.10 gives us "uncollidable channels"
by introducing an additional channel type -- ID-channels ("!channels") --
to IRC. An ID-channel (from now on only called "!channel" in contrast
to "#channel") is nothing more than a channel with a unique ID. The
channels that you know and regularly use have the form: #channel_name.
The new !channels have the form: !<ID>channel_short_name, where
<ID> is a
unique ID chosen by the IRC server, like "abd23" and "channel_short_name" is the channel name chosen by you, the user or
respectively, the creator of the channel. An example of some !channel
could be: !abd23France, where "!" is the prefix present in all
!channels, "abd23" is the channel ID and "France" is the short name.
The channel ID has always the same length, which makes it easier to
distinguish the short name from the ID.
Since each !channel has a unique ID, it's "impossible" to have
identical !channels and they are not collidable. Here are the basic
rules which you have to keep in mind when using the new !channels:
- You can only create a new !channel when there doesn't exist another
!channel with the same short name yet.
Example: If you try to create the !channel "foo" (for command syntax
see below), then this will only work when there's no existing
!channel "foo" yet, regardless of its ID. You won't be able to
create just another "foo" !channel with a different ID.
- On a netsplit (two parts of the net splitting up), when a former
existing !channel has been split away (ie. is situated on the other side of
the net, which is currently not connected to yours), then its name
(ID + short name) is being remembered for a certain amount of time
by the other part of the net. When you join such a !channel while it's
still being remembered by the server, then you won't get channel-op on
that channel. If you join it after that amount of time, then you
create a !channel with the same short name as the one that splitted away,
but with a different channel ID.
- Under some circumstances (see above), several !channels with the
same short name but with a different ID can exist. But if there's
only one !channel with the same given short name, then you can JOIN it
without having to supply its channel ID (see below).
- Only the JOIN and the LIST command also accept a !channel's short name only.
All other commands require the whole !channel name
- When there are several !channels with the same short name but
with a different ID, then you can chose which of them to join by indicating
the respective ID on the JOIN command.
Now that you know the basic rules concerning !channels, let's
examine the respective commands (especially the JOIN command) for the use of
those channels. A basic rule applies to the entire command section:
It may be possible that your current IRC client does not support
(yet) (entirely) the new !channels. So if some of the following commands
don't work for you or make your client look weird, then it's probably
your client's "fault".
This being said, here we go with a list of basic commands in relation to our
- /JOIN !!foo
This creates a new !channel with the short name "foo" and with an ID
assigned by the server. The entire name of the channel will then be:
"!<ID>foo" (example with an ID: "!sf34bfoo"). This will only
work if no !channel with the same short name ("foo") existed before.
- /JOIN !foo
Attempts to join the already existing !channel with the short name
"foo". Will only work, if a) a !channel with that short name already exists
and b) there is no more than one existing !channel with that short
name. If there are several !channels with the short name "foo" but
with different IDs, then this command won't work.
- /JOIN !<ID>foo
Attempts to join the already existing !channel with the short name
"foo" and with the indicated channel ID. Does only work, if a
!channel with that short name and exactly that ID already exists.
- /LIST !<ID>foo
Shows you the LIST output for the !channel "foo" with the given ID.
Does only work if the indicated channel (short name + ID) exists.
- /LIST !foo
Shows you all the 'foo' named channels out there. This is especially
useful, if /JOIN !foo fails, and you have to know the
exact channel ID to use /JOIN !<ID>foo then.
- /NAMES !<ID>foo
Same as for /LIST. As you can see, you can use all the other
commands with !channels too, as long as you use their full name (short name
A new user mode
Along with the new !channels was also introduced a new user mode,
which is closely related to the !channels. This new user mode is
automatically assigned to everyone who creates
a new !channel
and it makes him the "!channel creator" for each !channel he has created. The
sign of this new mode is "+O" (don't confuse this with the already existing user
mode "+o" which all channel operators have). The server gives you the
"+O" user mode for each !channel you created
. So if you create
the !channel "foo", then you will automatically get the user mode "+o"
(channel operator -- as usual) and also the user mode "+O" (!channel
creator) for the !channel "!<ID>foo".
Here are the characteristics of the new !channel creator mode (+O):
- It cannot be removed "manually".
- A !channel creator does only lose it for a given !channel when
he leaves that channel or gets deopped on that channel (-o).
- If a !channel creator leaves and then rejoins a !channel which
he created, then he will not get it again.
- If a !channel creator gets deopped and then reopped, he
wonīt get the creator status back.
- In order to see if a given !channel has still its !channel
creator, you have to type: "/MODE !<ID>channel O". If
the answer from the server contains "-O" then the !channelīs
creator has lost its creator flag and canīt win it back.
- A !channel creator can set/unset the new channel mode "r" (see
A new channel mode
Along with the !channels comes also a new !channel mode, the "reop"
channel mode, whose sign is "r". Only a !channel creator can add or
remove it. It can be set via the MODE command, just like any other already
existing channel mode (s, i, m, etc.). Its purpose is to avoid opless
!channels. Since !channels are unique and cannot be collided, it's
impossible to get "server-ops" on them by a !channel collision (contrary to
normal #channels) once they become opless.
So if a !channel should not risk to stay opless forever once it becomes
opless, its !channel creator has to set the "r" mode on it. If this
mode is set and the !channel becomes and stays opless for a while, then the
server will reop automatically and randomly some (or all) users on it.
The randomness of the reopping routine is programmed in a way that it
won't increase your chance to get reopped if you let lots of
clones/bots/friends, for example, join the !channel.
The main problem of IRCNet
nick collisions -- is still not addressed but will be solved in the next
major IRC server version. An interesting proposal to that problem
comes from Piotr "Beeth" Kucharski and can be found
Besides that, the whole IRC server software needs to be rewritten... :-)