RFC 2812
Network Working Group C. Kalt
Request for Comments: 2812 April 2000
Updates: 1459
Category: Informational
Internet Relay Chat: Client Protocol
Status of this Memo
This memo provides information for the Internet community. It does
not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice
Copyright (C) The Internet Society (2000). All Rights Reserved.
IESG NOTE:
The IRC protocol itself enables several possibilities of transferring
data between clients, and just like with other transfer mechanisms
like email, the receiver of the data has to be careful about how the
data is handled. For more information on security issues with the IRC
protocol, see for example http://www.irchelp.org/irchelp/security/.
Abstract
The IRC (Internet Relay Chat) protocol is for use with text based
conferencing; the simplest client being any socket program capable of
connecting to the server.
This document defines the Client Protocol, and assumes that the
reader is familiar with the IRC Architecture [IRC-ARCH].
Table of Contents
1. Labels ..................................................... 3
1.1 Servers ................................................ 3
1.2 Clients ................................................ 3
1.2.1 Users ............................................. 4
1.2.1.1 Operators .................................... 4
1.2.2 Services .......................................... 4
1.3 Channels ............................................... 4
2. The IRC Client Specification ............................... 5
2.1 Overview ............................................... 5
2.2 Character codes ........................................ 5
2.3 Messages ............................................... 5
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2.3.1 Message format in Augmented BNF ................... 6
2.4 Numeric replies ........................................ 8
2.5 Wildcard expressions ................................... 9
3. Message Details ............................................ 9
3.1 Connection Registration ................................ 10
3.1.1 Password message .................................. 10
3.1.2 Nick message ...................................... 10
3.1.3 User message ...................................... 11
3.1.4 Oper message ...................................... 12
3.1.5 User mode message ................................. 12
3.1.6 Service message ................................... 13
3.1.7 Quit .............................................. 14
3.1.8 Squit ............................................. 15
3.2 Channel operations ..................................... 15
3.2.1 Join message ...................................... 16
3.2.2 Part message ...................................... 17
3.2.3 Channel mode message .............................. 18
3.2.4 Topic message ..................................... 19
3.2.5 Names message ..................................... 20
3.2.6 List message ...................................... 21
3.2.7 Invite message .................................... 21
3.2.8 Kick command ...................................... 22
3.3 Sending messages ....................................... 23
3.3.1 Private messages .................................. 23
3.3.2 Notice ............................................ 24
3.4 Server queries and commands ............................ 25
3.4.1 Motd message ...................................... 25
3.4.2 Lusers message .................................... 25
3.4.3 Version message ................................... 26
3.4.4 Stats message ..................................... 26
3.4.5 Links message ..................................... 27
3.4.6 Time message ...................................... 28
3.4.7 Connect message ................................... 28
3.4.8 Trace message ..................................... 29
3.4.9 Admin command ..................................... 30
3.4.10 Info command ...................................... 31
3.5 Service Query and Commands ............................. 31
3.5.1 Servlist message .................................. 31
3.5.2 Squery ............................................ 32
3.6 User based queries ..................................... 32
3.6.1 Who query ......................................... 32
3.6.2 Whois query ....................................... 33
3.6.3 Whowas ............................................ 34
3.7 Miscellaneous messages ................................. 34
3.7.1 Kill message ...................................... 35
3.7.2 Ping message ...................................... 36
3.7.3 Pong message ...................................... 37
3.7.4 Error ............................................. 37
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4. Optional features .......................................... 38
4.1 Away ................................................... 38
4.2 Rehash message ......................................... 39
4.3 Die message ............................................ 39
4.4 Restart message ........................................ 40
4.5 Summon message ......................................... 40
4.6 Users .................................................. 41
4.7 Operwall message ....................................... 41
4.8 Userhost message ....................................... 42
4.9 Ison message ........................................... 42
5. Replies .................................................... 43
5.1 Command responses ...................................... 43
5.2 Error Replies .......................................... 53
5.3 Reserved numerics ...................................... 59
6. Current implementations .................................... 60
7. Current problems ........................................... 60
7.1 Nicknames .............................................. 60
7.2 Limitation of wildcards ................................ 61
7.3 Security considerations ................................ 61
8. Current support and availability ........................... 61
9. Acknowledgements ........................................... 61
10. References ................................................ 62
11. Author's Address .......................................... 62
12. Full Copyright Statement .................................. 63
1. Labels
This section defines the identifiers used for the various components
of the IRC protocol.
1.1 Servers
Servers are uniquely identified by their name, which has a maximum
length of sixty three (63) characters. See the protocol grammar
rules (section 2.3.1) for what may and may not be used in a server
name.
1.2 Clients
For each client all servers MUST have the following information: a
netwide unique identifier (whose format depends on the type of
client) and the server which introduced the client.
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1.2.1 Users
Each user is distinguished from other users by a unique nickname
having a maximum length of nine (9) characters. See the protocol
grammar rules (section 2.3.1) for what may and may not be used in a
nickname.
While the maximum length is limited to nine characters, clients
SHOULD accept longer strings as they may become used in future
evolutions of the protocol.
1.2.1.1 Operators
To allow a reasonable amount of order to be kept within the IRC
network, a special class of users (operators) is allowed to perform
general maintenance functions on the network. Although the powers
granted to an operator can be considered as 'dangerous', they are
nonetheless often necessary. Operators SHOULD be able to perform
basic network tasks such as disconnecting and reconnecting servers as
needed. In recognition of this need, the protocol discussed herein
provides for operators only to be able to perform such functions.
See sections 3.1.8 (SQUIT) and 3.4.7 (CONNECT).
A more controversial power of operators is the ability to remove a
user from the connected network by 'force', i.e., operators are able
to close the connection between any client and server. The
justification for this is very delicate since its abuse is both
destructive and annoying, and its benefits close to inexistent. For
further details on this type of action, see section 3.7.1 (KILL).
1.2.2 Services
Each service is distinguished from other services by a service name
composed of a nickname and a server name. As for users, the nickname
has a maximum length of nine (9) characters. See the protocol
grammar rules (section 2.3.1) for what may and may not be used in a
nickname.
1.3 Channels
Channels names are strings (beginning with a '&', '#', '+' or '!'
character) of length up to fifty (50) characters. Apart from the
requirement that the first character is either '&', '#', '+' or '!',
the only restriction on a channel name is that it SHALL NOT contain
any spaces (' '), a control G (^G or ASCII 7), a comma (','). Space
is used as parameter separator and command is used as a list item
separator by the protocol). A colon (':') can also be used as a
delimiter for the channel mask. Channel names are case insensitive.
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See the protocol grammar rules (section 2.3.1) for the exact syntax
of a channel name.
Each prefix characterizes a different channel type. The definition
of the channel types is not relevant to the client-server protocol
and thus it is beyond the scope of this document. More details can
be found in "Internet Relay Chat: Channel Management" [IRC-CHAN].
2. The IRC Client Specification
2.1 Overview
The protocol as described herein is for use only with client to
server connections when the client registers as a user.
2.2 Character codes
No specific character set is specified. The protocol is based on a
set of codes which are composed of eight (8) bits, making up an
octet. Each message may be composed of any number of these octets;
however, some octet values are used for control codes, which act as
message delimiters.
Regardless of being an 8-bit protocol, the delimiters and keywords
are such that protocol is mostly usable from US-ASCII terminal and a
telnet connection.
Because of IRC's Scandinavian origin, the characters {}|^ are
considered to be the lower case equivalents of the characters []\~,
respectively. This is a critical issue when determining the
equivalence of two nicknames or channel names.
2.3 Messages
Servers and clients send each other messages, which may or may not
generate a reply. If the message contains a valid command, as
described in later sections, the client should expect a reply as
specified but it is not advised to wait forever for the reply; client
to server and server to server communication is essentially
asynchronous by nature.
Each IRC message may consist of up to three main parts: the prefix
(OPTIONAL), the command, and the command parameters (maximum of
fifteen (15)). The prefix, command, and all parameters are separated
by one ASCII space character (0x20) each.
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The presence of a prefix is indicated with a single leading ASCII
colon character (':', 0x3b), which MUST be the first character of the
message itself. There MUST be NO gap (whitespace) between the colon
and the prefix. The prefix is used by servers to indicate the true
origin of the message. If the prefix is missing from the message, it
is assumed to have originated from the connection from which it was
received from. Clients SHOULD NOT use a prefix when sending a
message; if they use one, the only valid prefix is the registered
nickname associated with the client.
The command MUST either be a valid IRC command or a three (3) digit
number represented in ASCII text.
IRC messages are always lines of characters terminated with a CR-LF
(Carriage Return - Line Feed) pair, and these messages SHALL NOT
exceed 512 characters in length, counting all characters including
the trailing CR-LF. Thus, there are 510 characters maximum allowed
for the command and its parameters. There is no provision for
continuation of message lines. See section 6 for more details about
current implementations.
2.3.1 Message format in Augmented BNF
The protocol messages must be extracted from the contiguous stream of
octets. The current solution is to designate two characters, CR and
LF, as message separators. Empty messages are silently ignored,
which permits use of the sequence CR-LF between messages without
extra problems.
The extracted message is parsed into the components <prefix>,
<command> and list of parameters (<params>).
The Augmented BNF representation for this is:
message = [ ":" prefix SPACE ] command [ params ] crlf
prefix = servername / ( nickname [ [ "!" user ] "@" host ] )
command = 1*letter / 3digit
params = *14( SPACE middle ) [ SPACE ":" trailing ]
=/ 14( SPACE middle ) [ SPACE [ ":" ] trailing ]
nospcrlfcl = %x01-09 / %x0B-0C / %x0E-1F / %x21-39 / %x3B-FF
; any octet except NUL, CR, LF, " " and ":"
middle = nospcrlfcl *( ":" / nospcrlfcl )
trailing = *( ":" / " " / nospcrlfcl )
SPACE = %x20 ; space character
crlf = %x0D %x0A ; "carriage return" "linefeed"
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NOTES:
1) After extracting the parameter list, all parameters are equal
whether matched by <middle> or <trailing>. <trailing> is just a
syntactic trick to allow SPACE within the parameter.
2) The NUL (%x00) character is not special in message framing, and
basically could end up inside a parameter, but it would cause
extra complexities in normal C string handling. Therefore, NUL
is not allowed within messages.
Most protocol messages specify additional semantics and syntax for
the extracted parameter strings dictated by their position in the
list. For example, many server commands will assume that the first
parameter after the command is the list of targets, which can be
described with:
target = nickname / server
msgtarget = msgto *( "," msgto )
msgto = channel / ( user [ "%" host ] "@" servername )
msgto =/ ( user "%" host ) / targetmask
msgto =/ nickname / ( nickname "!" user "@" host )
channel = ( "#" / "+" / ( "!" channelid ) / "&" ) chanstring
[ ":" chanstring ]
servername = hostname
host = hostname / hostaddr
hostname = shortname *( "." shortname )
shortname = ( letter / digit ) *( letter / digit / "-" )
*( letter / digit )
; as specified in RFC 1123 [HNAME]
hostaddr = ip4addr / ip6addr
ip4addr = 1*3digit "." 1*3digit "." 1*3digit "." 1*3digit
ip6addr = 1*hexdigit 7( ":" 1*hexdigit )
ip6addr =/ "0:0:0:0:0:" ( "0" / "FFFF" ) ":" ip4addr
nickname = ( letter / special ) *8( letter / digit / special / "-" )
targetmask = ( "$" / "#" ) mask
; see details on allowed masks in section 3.3.1
chanstring = %x01-07 / %x08-09 / %x0B-0C / %x0E-1F / %x21-2B
chanstring =/ %x2D-39 / %x3B-FF
; any octet except NUL, BELL, CR, LF, " ", "," and ":"
channelid = 5( %x41-5A / digit ) ; 5( A-Z / 0-9 )
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Other parameter syntaxes are:
user = 1*( %x01-09 / %x0B-0C / %x0E-1F / %x21-3F / %x41-FF )
; any octet except NUL, CR, LF, " " and "@"
key = 1*23( %x01-05 / %x07-08 / %x0C / %x0E-1F / %x21-7F )
; any 7-bit US_ASCII character,
; except NUL, CR, LF, FF, h/v TABs, and " "
letter = %x41-5A / %x61-7A ; A-Z / a-z
digit = %x30-39 ; 0-9
hexdigit = digit / "A" / "B" / "C" / "D" / "E" / "F"
special = %x5B-60 / %x7B-7D
; "[", "]", "\", "`", "_", "^", "{", "|", "}"
NOTES:
1) The <hostaddr> syntax is given here for the sole purpose of
indicating the format to follow for IP addresses. This
reflects the fact that the only available implementations of
this protocol uses TCP/IP as underlying network protocol but is
not meant to prevent other protocols to be used.
2) <hostname> has a maximum length of 63 characters. This is a
limitation of the protocol as internet hostnames (in
particular) can be longer. Such restriction is necessary
because IRC messages are limited to 512 characters in length.
Clients connecting from a host which name is longer than 63
characters are registered using the host (numeric) address
instead of the host name.
3) Some parameters used in the following sections of this
documents are not defined here as there is nothing specific
about them besides the name that is used for convenience.
These parameters follow the general syntax defined for
<params>.
2.4 Numeric replies
Most of the messages sent to the server generate a reply of some
sort. The most common reply is the numeric reply, used for both
errors and normal replies. The numeric reply MUST be sent as one
message consisting of the sender prefix, the three-digit numeric, and
the target of the reply. A numeric reply is not allowed to originate
from a client. In all other respects, a numeric reply is just like a
normal message, except that the keyword is made up of 3 numeric
digits rather than a string of letters. A list of different replies
is supplied in section 5 (Replies).
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2.5 Wildcard expressions
When wildcards are allowed in a string, it is referred as a "mask".
For string matching purposes, the protocol allows the use of two
special characters: '?' (%x3F) to match one and only one character,
and '*' (%x2A) to match any number of any characters. These two
characters can be escaped using the character '\' (%x5C).
The Augmented BNF syntax for this is:
mask = *( nowild / noesc wildone / noesc wildmany )
wildone = %x3F
wildmany = %x2A
nowild = %x01-29 / %x2B-3E / %x40-FF
; any octet except NUL, "*", "?"
noesc = %x01-5B / %x5D-FF
; any octet except NUL and "\"
matchone = %x01-FF
; matches wildone
matchmany = *matchone
; matches wildmany
Examples:
a?c ; Matches any string of 3 characters in length starting
with "a" and ending with "c"
a*c ; Matches any string of at least 2 characters in length
starting with "a" and ending with "c"
3. Message Details
On the following pages there are descriptions of each message
recognized by the IRC server and client. All commands described in
this section MUST be implemented by any server for this protocol.
Where the reply ERR_NOSUCHSERVER is returned, it means that the
target of the message could not be found. The server MUST NOT send
any other replies after this error for that command.
The server to which a client is connected is required to parse the
complete message, and return any appropriate errors.
If multiple parameters is presented, then each MUST be checked for
validity and appropriate responses MUST be sent back to the client.
In the case of incorrect messages which use parameter lists with
comma as an item separator, a reply MUST be sent for each item.
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3.1 Connection Registration
The commands described here are used to register a connection with an
IRC server as a user as well as to correctly disconnect.
A "PASS" command is not required for a client connection to be
registered, but it MUST precede the latter of the NICK/USER
combination (for a user connection) or the SERVICE command (for a
service connection). The RECOMMENDED order for a client to register
is as follows:
1. Pass message
2. Nick message 2. Service message
3. User message
Upon success, the client will receive an RPL_WELCOME (for users) or
RPL_YOURESERVICE (for services) message indicating that the
connection is now registered and known the to the entire IRC network.
The reply message MUST contain the full client identifier upon which
it was registered.
3.1.1 Password message
Command: PASS
Parameters: <password>
The PASS command is used to set a 'connection password'. The
optional password can and MUST be set before any attempt to register
the connection is made. Currently this requires that user send a
PASS command before sending the NICK/USER combination.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_ALREADYREGISTRED
Example:
PASS secretpasswordhere
3.1.2 Nick message
Command: NICK
Parameters: <nickname>
NICK command is used to give user a nickname or change the existing
one.
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Numeric Replies:
ERR_NONICKNAMEGIVEN ERR_ERRONEUSNICKNAME
ERR_NICKNAMEINUSE ERR_NICKCOLLISION
ERR_UNAVAILRESOURCE ERR_RESTRICTED
Examples:
NICK Wiz ; Introducing new nick "Wiz" if session is
still unregistered, or user changing his
nickname to "Wiz"
:WiZ!jto@tolsun.oulu.fi NICK Kilroy
; Server telling that WiZ changed his
nickname to Kilroy.
3.1.3 User message
Command: USER
Parameters: <user> <mode> <unused> <realname>
The USER command is used at the beginning of connection to specify
the username, hostname and realname of a new user.
The <mode> parameter should be a numeric, and can be used to
automatically set user modes when registering with the server. This
parameter is a bitmask, with only 2 bits having any signification: if
the bit 2 is set, the user mode 'w' will be set and if the bit 3 is
set, the user mode 'i' will be set. (See Section 3.1.5 "User
Modes").
The <realname> may contain space characters.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_ALREADYREGISTRED
Example:
USER guest 0 * :Ronnie Reagan ; User registering themselves with a
username of "guest" and real name
"Ronnie Reagan".
USER guest 8 * :Ronnie Reagan ; User registering themselves with a
username of "guest" and real name
"Ronnie Reagan", and asking to be set
invisible.
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3.1.4 Oper message
Command: OPER
Parameters: <name> <password>
A normal user uses the OPER command to obtain operator privileges.
The combination of <name> and <password> are REQUIRED to gain
Operator privileges. Upon success, the user will receive a MODE
message (see section 3.1.5) indicating the new user modes.
Numeric Replies:
ERR_NEEDMOREPARAMS RPL_YOUREOPER
ERR_NOOPERHOST ERR_PASSWDMISMATCH
Example:
OPER foo bar ; Attempt to register as an operator
using a username of "foo" and "bar"
as the password.
3.1.5 User mode message
Command: MODE
Parameters: <nickname>
*( ( "+" / "-" ) *( "i" / "w" / "o" / "O" / "r" ) )
The user MODE's are typically changes which affect either how the
client is seen by others or what 'extra' messages the client is sent.
A user MODE command MUST only be accepted if both the sender of the
message and the nickname given as a parameter are both the same. If
no other parameter is given, then the server will return the current
settings for the nick.
The available modes are as follows:
a - user is flagged as away;
i - marks a users as invisible;
w - user receives wallops;
r - restricted user connection;
o - operator flag;
O - local operator flag;
s - marks a user for receipt of server notices.
Additional modes may be available later on.
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The flag 'a' SHALL NOT be toggled by the user using the MODE command,
instead use of the AWAY command is REQUIRED.
If a user attempts to make themselves an operator using the "+o" or
"+O" flag, the attempt SHOULD be ignored as users could bypass the
authentication mechanisms of the OPER command. There is no
restriction, however, on anyone `deopping' themselves (using "-o" or
"-O").
On the other hand, if a user attempts to make themselves unrestricted
using the "-r" flag, the attempt SHOULD be ignored. There is no
restriction, however, on anyone `deopping' themselves (using "+r").
This flag is typically set by the server upon connection for
administrative reasons. While the restrictions imposed are left up
to the implementation, it is typical that a restricted user not be
allowed to change nicknames, nor make use of the channel operator
status on channels.
The flag 's' is obsolete but MAY still be used.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_USERSDONTMATCH
ERR_UMODEUNKNOWNFLAG RPL_UMODEIS
Examples:
MODE WiZ -w ; Command by WiZ to turn off
reception of WALLOPS messages.
MODE Angel +i ; Command from Angel to make herself
invisible.
MODE WiZ -o ; WiZ 'deopping' (removing operator
status).
3.1.6 Service message
Command: SERVICE
Parameters: <nickname> <reserved> <distribution> <type>
<reserved> <info>
The SERVICE command to register a new service. Command parameters
specify the service nickname, distribution, type and info of a new
service.
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The <distribution> parameter is used to specify the visibility of a
service. The service may only be known to servers which have a name
matching the distribution. For a matching server to have knowledge
of the service, the network path between that server and the server
on which the service is connected MUST be composed of servers which
names all match the mask.
The <type> parameter is currently reserved for future usage.
Numeric Replies:
ERR_ALREADYREGISTRED ERR_NEEDMOREPARAMS
ERR_ERRONEUSNICKNAME
RPL_YOURESERVICE RPL_YOURHOST
RPL_MYINFO
Example:
SERVICE dict * *.fr 0 0 :French Dictionary ; Service registering
itself with a name of "dict". This
service will only be available on
servers which name matches "*.fr".
3.1.7 Quit
Command: QUIT
Parameters: [ <Quit Message> ]
A client session is terminated with a quit message. The server
acknowledges this by sending an ERROR message to the client.
Numeric Replies:
None.
Example:
QUIT :Gone to have lunch ; Preferred message format.
:syrk!kalt@millennium.stealth.net QUIT :Gone to have lunch ; User
syrk has quit IRC to have lunch.
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3.1.8 Squit
Command: SQUIT
Parameters: <server> <comment>
The SQUIT command is available only to operators. It is used to
disconnect server links. Also servers can generate SQUIT messages on
error conditions. A SQUIT message may also target a remote server
connection. In this case, the SQUIT message will simply be sent to
the remote server without affecting the servers in between the
operator and the remote server.
The <comment> SHOULD be supplied by all operators who execute a SQUIT
for a remote server. The server ordered to disconnect its peer
generates a WALLOPS message with <comment> included, so that other
users may be aware of the reason of this action.
Numeric replies:
ERR_NOPRIVILEGES ERR_NOSUCHSERVER
ERR_NEEDMOREPARAMS
Examples:
SQUIT tolsun.oulu.fi :Bad Link ? ; Command to uplink of the server
tolson.oulu.fi to terminate its
connection with comment "Bad Link".
:Trillian SQUIT cm22.eng.umd.edu :Server out of control ; Command
from Trillian from to disconnect
"cm22.eng.umd.edu" from the net with
comment "Server out of control".
3.2 Channel operations
This group of messages is concerned with manipulating channels, their
properties (channel modes), and their contents (typically users).
For this reason, these messages SHALL NOT be made available to
services.
All of these messages are requests which will or will not be granted
by the server. The server MUST send a reply informing the user
whether the request was granted, denied or generated an error. When
the server grants the request, the message is typically sent back
(eventually reformatted) to the user with the prefix set to the user
itself.
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The rules governing how channels are managed are enforced by the
servers. These rules are beyond the scope of this document. More
details are found in "Internet Relay Chat: Channel Management" [IRC-
CHAN].
3.2.1 Join message
Command: JOIN
Parameters: ( <channel> *( "," <channel> ) [ <key> *( "," <key> ) ] )
/ "0"
The JOIN command is used by a user to request to start listening to
the specific channel. Servers MUST be able to parse arguments in the
form of a list of target, but SHOULD NOT use lists when sending JOIN
messages to clients.
Once a user has joined a channel, he receives information about
all commands his server receives affecting the channel. This
includes JOIN, MODE, KICK, PART, QUIT and of course PRIVMSG/NOTICE.
This allows channel members to keep track of the other channel
members, as well as channel modes.
If a JOIN is successful, the user receives a JOIN message as
confirmation and is then sent the channel's topic (using RPL_TOPIC) and
the list of users who are on the channel (using RPL_NAMREPLY), which
MUST include the user joining.
Note that this message accepts a special argument ("0"), which is
a special request to leave all channels the user is currently a member
of. The server will process this message as if the user had sent
a PART command (See Section 3.2.2) for each channel he is a member
of.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_BANNEDFROMCHAN
ERR_INVITEONLYCHAN ERR_BADCHANNELKEY
ERR_CHANNELISFULL ERR_BADCHANMASK
ERR_NOSUCHCHANNEL ERR_TOOMANYCHANNELS
ERR_TOOMANYTARGETS ERR_UNAVAILRESOURCE
RPL_TOPIC
Examples:
JOIN #foobar ; Command to join channel #foobar.
JOIN &foo fubar ; Command to join channel &foo using
key "fubar".
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JOIN #foo,&bar fubar ; Command to join channel #foo using
key "fubar" and &bar using no key.
JOIN #foo,#bar fubar,foobar ; Command to join channel #foo using
key "fubar", and channel #bar using
key "foobar".
JOIN #foo,#bar ; Command to join channels #foo and
#bar.
JOIN 0 ; Leave all currently joined
channels.
:WiZ!jto@tolsun.oulu.fi JOIN #Twilight_zone ; JOIN message from WiZ
on channel #Twilight_zone
3.2.2 Part message
Command: PART
Parameters: <channel> *( "," <channel> ) [ <Part Message> ]
The PART command causes the user sending the message to be removed
from the list of active members for all given channels listed in the
parameter string. If a "Part Message" is given, this will be sent
instead of the default message, the nickname. This request is always
granted by the server.
Servers MUST be able to parse arguments in the form of a list of
target, but SHOULD NOT use lists when sending PART messages to
clients.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_NOSUCHCHANNEL
ERR_NOTONCHANNEL
Examples:
PART #twilight_zone ; Command to leave channel
"#twilight_zone"
PART #oz-ops,&group5 ; Command to leave both channels
"&group5" and "#oz-ops".
:WiZ!jto@tolsun.oulu.fi PART #playzone :I lost
; User WiZ leaving channel
"#playzone" with the message "I
lost".
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3.2.3 Channel mode message
Command: MODE
Parameters: <channel> *( ( "-" / "+" ) *<modes> *<modeparams> )
The MODE command is provided so that users may query and change the
characteristics of a channel. For more details on available modes
and their uses, see "Internet Relay Chat: Channel Management" [IRC-
CHAN]. Note that there is a maximum limit of three (3) changes per
command for modes that take a parameter.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_KEYSET
ERR_NOCHANMODES ERR_CHANOPRIVSNEEDED
ERR_USERNOTINCHANNEL ERR_UNKNOWNMODE
RPL_CHANNELMODEIS
RPL_BANLIST RPL_ENDOFBANLIST
RPL_EXCEPTLIST RPL_ENDOFEXCEPTLIST
RPL_INVITELIST RPL_ENDOFINVITELIST
RPL_UNIQOPIS
The following examples are given to help understanding the syntax of
the MODE command, but refer to modes defined in "Internet Relay Chat:
Channel Management" [IRC-CHAN].
Examples:
MODE #Finnish +imI *!*@*.fi ; Command to make #Finnish channel
moderated and 'invite-only' with user
with a hostname matching *.fi
automatically invited.
MODE #Finnish +o Kilroy ; Command to give 'chanop' privileges
to Kilroy on channel #Finnish.
MODE #Finnish +v Wiz ; Command to allow WiZ to speak on
#Finnish.
MODE #Fins -s ; Command to remove 'secret' flag
from channel #Fins.
MODE #42 +k oulu ; Command to set the channel key to
"oulu".
MODE #42 -k oulu ; Command to remove the "oulu"
channel key on channel "#42".
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MODE #eu-opers +l 10 ; Command to set the limit for the
number of users on channel
"#eu-opers" to 10.
:WiZ!jto@tolsun.oulu.fi MODE #eu-opers -l
; User "WiZ" removing the limit for
the number of users on channel "#eu-
opers".
MODE &oulu +b ; Command to list ban masks set for
the channel "&oulu".
MODE &oulu +b *!*@* ; Command to prevent all users from
joining.
MODE &oulu +b *!*@*.edu +e *!*@*.bu.edu
; Command to prevent any user from a
hostname matching *.edu from joining,
except if matching *.bu.edu
MODE #bu +be *!*@*.edu *!*@*.bu.edu
; Comment to prevent any user from a
hostname matching *.edu from joining,
except if matching *.bu.edu
MODE #meditation e ; Command to list exception masks set
for the channel "#meditation".
MODE #meditation I ; Command to list invitations masks
set for the channel "#meditation".
MODE !12345ircd O ; Command to ask who the channel
creator for "!12345ircd" is
3.2.4 Topic message
Command: TOPIC
Parameters: <channel> [ <topic> ]
The TOPIC command is used to change or view the topic of a channel.
The topic for channel <channel> is returned if there is no <topic>
given. If the <topic> parameter is present, the topic for that
channel will be changed, if this action is allowed for the user
requesting it. If the <topic> parameter is an empty string, the
topic for that channel will be removed.
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Numeric Replies:
ERR_NEEDMOREPARAMS ERR_NOTONCHANNEL
RPL_NOTOPIC RPL_TOPIC
ERR_CHANOPRIVSNEEDED ERR_NOCHANMODES
Examples:
:WiZ!jto@tolsun.oulu.fi TOPIC #test :New topic ; User Wiz setting the
topic.
TOPIC #test :another topic ; Command to set the topic on #test
to "another topic".
TOPIC #test : ; Command to clear the topic on
#test.
TOPIC #test ; Command to check the topic for
#test.
3.2.5 Names message
Command: NAMES
Parameters: [ <channel> *( "," <channel> ) [ <target> ] ]
By using the NAMES command, a user can list all nicknames that are
visible to him. For more details on what is visible and what is not,
see "Internet Relay Chat: Channel Management" [IRC-CHAN]. The
<channel> parameter specifies which channel(s) to return information
about. There is no error reply for bad channel names.
If no <channel> parameter is given, a list of all channels and their
occupants is returned. At the end of this list, a list of users who
are visible but either not on any channel or not on a visible channel
are listed as being on `channel' "*".
If the <target> parameter is specified, the request is forwarded to
that server which will generate the reply.
Wildcards are allowed in the <target> parameter.
Numerics:
ERR_TOOMANYMATCHES ERR_NOSUCHSERVER
RPL_NAMREPLY RPL_ENDOFNAMES
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Examples:
NAMES #twilight_zone,#42 ; Command to list visible users on
#twilight_zone and #42
NAMES ; Command to list all visible
channels and users
3.2.6 List message
Command: LIST
Parameters: [ <channel> *( "," <channel> ) [ <target> ] ]
The list command is used to list channels and their topics. If the
<channel> parameter is used, only the status of that channel is
displayed.
If the <target> parameter is specified, the request is forwarded to
that server which will generate the reply.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_TOOMANYMATCHES ERR_NOSUCHSERVER
RPL_LIST RPL_LISTEND
Examples:
LIST ; Command to list all channels.
LIST #twilight_zone,#42 ; Command to list channels
#twilight_zone and #42
3.2.7 Invite message
Command: INVITE
Parameters: <nickname> <channel>
The INVITE command is used to invite a user to a channel. The
parameter <nickname> is the nickname of the person to be invited to
the target channel <channel>. There is no requirement that the
channel the target user is being invited to must exist or be a valid
channel. However, if the channel exists, only members of the channel
are allowed to invite other users. When the channel has invite-only
flag set, only channel operators may issue INVITE command.
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Only the user inviting and the user being invited will receive
notification of the invitation. Other channel members are not
notified. (This is unlike the MODE changes, and is occasionally the
source of trouble for users.)
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_NOSUCHNICK
ERR_NOTONCHANNEL ERR_USERONCHANNEL
ERR_CHANOPRIVSNEEDED
RPL_INVITING RPL_AWAY
Examples:
:Angel!wings@irc.org INVITE Wiz #Dust
; Message to WiZ when he has been
invited by user Angel to channel
#Dust
INVITE Wiz #Twilight_Zone ; Command to invite WiZ to
#Twilight_zone
3.2.8 Kick command
Command: KICK
Parameters: <channel> *( "," <channel> ) <user> *( "," <user> )
[<comment>]
The KICK command can be used to request the forced removal of a user
from a channel. It causes the <user> to PART from the <channel> by
force. For the message to be syntactically correct, there MUST be
either one channel parameter and multiple user parameter, or as many
channel parameters as there are user parameters. If a "comment" is
given, this will be sent instead of the default message, the nickname
of the user issuing the KICK.
The server MUST NOT send KICK messages with multiple channels or
users to clients. This is necessarily to maintain backward
compatibility with old client software.
Numeric Replies:
ERR_NEEDMOREPARAMS ERR_NOSUCHCHANNEL
ERR_BADCHANMASK ERR_CHANOPRIVSNEEDED
ERR_USERNOTINCHANNEL ERR_NOTONCHANNEL
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Examples:
KICK &Melbourne Matthew ; Command to kick Matthew from
&Melbourne
KICK #Finnish John :Speaking English
; Command to kick John from #Finnish
using "Speaking English" as the
reason (comment).
:WiZ!jto@tolsun.oulu.fi KICK #Finnish John
; KICK message on channel #Finnish
from WiZ to remove John from channel
3.3 Sending messages
The main purpose of the IRC protocol is to provide a base for clients
to communicate with each other. PRIVMSG, NOTICE and SQUERY
(described in Section 3.5 on Service Query and Commands) are the only
messages available which actually perform delivery of a text message
from one client to another - the rest just make it possible and try
to ensure it happens in a reliable and structured manner.
3.3.1 Private messages
Command: PRIVMSG
Parameters: <msgtarget> <text to be sent>
PRIVMSG is used to send private messages between users, as well as to
send messages to channels. <msgtarget> is usually the nickname of
the recipient of the message, or a channel name.
The <msgtarget> parameter may also be a host mask (#<mask>) or server
mask ($<mask>). In both cases the server will only send the PRIVMSG
to those who have a server or host matching the mask. The mask MUST
have at least 1 (one) "." in it and no wildcards following the last
".". This requirement exists to prevent people sending messages to
"#*" or "$*", which would broadcast to all users. Wildcards are the
'*' and '?' characters. This extension to the PRIVMSG command is
only available to operators.
Numeric Replies:
ERR_NORECIPIENT ERR_NOTEXTTOSEND
ERR_CANNOTSENDTOCHAN ERR_NOTOPLEVEL
ERR_WILDTOPLEVEL ERR_TOOMANYTARGETS
ERR_NOSUCHNICK
RPL_AWAY
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Examples:
:Angel!wings@irc.org PRIVMSG Wiz :Are you receiving this message ?
; Message from Angel to Wiz.
PRIVMSG Angel :yes I'm receiving it !
; Command to send a message to Angel.
PRIVMSG jto@tolsun.oulu.fi :Hello !
; Command to send a message to a user
on server tolsun.oulu.fi with
username of "jto".
PRIVMSG kalt%millennium.stealth.net@irc.stealth.net :Are you a frog?
; Message to a user on server
irc.stealth.net with username of
"kalt", and connected from the host
millennium.stealth.net.
PRIVMSG kalt%millennium.stealth.net :Do you like cheese?
; Message to a user on the local
server with username of "kalt", and
connected from the host
millennium.stealth.net.
PRIVMSG Wiz!jto@tolsun.oulu.fi :Hello !
; Message to the user with nickname
Wiz who is connected from the host
tolsun.oulu.fi and has the username
"jto".
PRIVMSG $*.fi :Server tolsun.oulu.fi rebooting.
; Message to everyone on a server
which has a name matching *.fi.
PRIVMSG #*.edu :NSFNet is undergoing work, expect interruptions
; Message to all users who come from
a host which has a name matching
*.edu.
3.3.2 Notice
Command: NOTICE
Parameters: <msgtarget> <text>
The NOTICE command is used similarly to PRIVMSG. The difference
between NOTICE and PRIVMSG is that automatic replies MUST NEVER be
sent in response to a NOTICE message. This rule applies to servers
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too - they MUST NOT send any error reply back to the client on
receipt of a notice. The object of this rule is to avoid loops
between clients automatically sending something in response to
something it received.
This command is available to services as well as users.
This is typically used by services, and automatons (clients with
either an AI or other interactive program controlling their actions).
See PRIVMSG for more details on replies and examples.
3.4 Server queries and commands
The server query group of commands has been designed to return
information about any server which is connected to the network.
In these queries, where a parameter appears as <target>, wildcard
masks are usually valid. For each parameter, however, only one query
and set of replies is to be generated. In most cases, if a nickname
is given, it will mean the server to which the user is connected.
These messages typically have little value for services, it is
therefore RECOMMENDED to forbid services from using them.
3.4.1 Motd message
Command: MOTD
Parameters: [ <target> ]
The MOTD command is used to get the "Message Of The Day" of the given
server, or current server if <target> is omitted.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
RPL_MOTDSTART RPL_MOTD
RPL_ENDOFMOTD ERR_NOMOTD
3.4.2 Lusers message
Command: LUSERS
Parameters: [ <mask> [ <target> ] ]
The LUSERS command is used to get statistics about the size of the
IRC network. If no parameter is given, the reply will be about the
whole net. If a <mask> is specified, then the reply will only
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concern the part of the network formed by the servers matching the
mask. Finally, if the <target> parameter is specified, the request
is forwarded to that server which will generate the reply.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
RPL_LUSERCLIENT RPL_LUSEROP
RPL_LUSERUNKOWN RPL_LUSERCHANNELS
RPL_LUSERME ERR_NOSUCHSERVER
3.4.3 Version message
Command: VERSION
Parameters: [ <target> ]
The VERSION command is used to query the version of the server
program. An optional parameter <target> is used to query the version
of the server program which a client is not directly connected to.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NOSUCHSERVER RPL_VERSION
Examples:
VERSION tolsun.oulu.fi ; Command to check the version of
server "tolsun.oulu.fi".
3.4.4 Stats message
Command: STATS
Parameters: [ <query> [ <target> ] ]
The stats command is used to query statistics of certain server. If
<query> parameter is omitted, only the end of stats reply is sent
back.
A query may be given for any single letter which is only checked by
the destination server and is otherwise passed on by intermediate
servers, ignored and unaltered.
Wildcards are allowed in the <target> parameter.
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Except for the ones below, the list of valid queries is
implementation dependent. The standard queries below SHOULD be
supported by the server:
l - returns a list of the server's connections, showing how
long each connection has been established and the
traffic over that connection in Kbytes and messages for
each direction;
m - returns the usage count for each of commands supported
by the server; commands for which the usage count is
zero MAY be omitted;
o - returns a list of configured privileged users,
operators;
u - returns a string showing how long the server has been
up.
It is also RECOMMENDED that client and server access configuration be
published this way.
Numeric Replies:
ERR_NOSUCHSERVER
RPL_STATSLINKINFO RPL_STATSUPTIME
RPL_STATSCOMMANDS RPL_STATSOLINE
RPL_ENDOFSTATS
Examples:
STATS m ; Command to check the command usage
for the server you are connected to
3.4.5 Links message
Command: LINKS
Parameters: [ [ <remote server> ] <server mask> ]
With LINKS, a user can list all servernames, which are known by the
server answering the query. The returned list of servers MUST match
the mask, or if no mask is given, the full list is returned.
If <remote server> is given in addition to <server mask>, the LINKS
command is forwarded to the first server found that matches that name
(if any), and that server is then required to answer the query.
Numeric Replies:
ERR_NOSUCHSERVER
RPL_LINKS RPL_ENDOFLINKS
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Examples:
LINKS *.au ; Command to list all servers which
have a name that matches *.au;
LINKS *.edu *.bu.edu ; Command to list servers matching
*.bu.edu as seen by the first server
matching *.edu.
3.4.6 Time message
Command: TIME
Parameters: [ <target> ]
The time command is used to query local time from the specified
server. If the <target> parameter is not given, the server receiving
the command must reply to the query.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NOSUCHSERVER RPL_TIME
Examples:
TIME tolsun.oulu.fi ; check the time on the server
"tolson.oulu.fi"
3.4.7 Connect message
Command: CONNECT
Parameters: <target server> <port> [ <remote server> ]
The CONNECT command can be used to request a server to try to
establish a new connection to another server immediately. CONNECT is
a privileged command and SHOULD be available only to IRC Operators.
If a <remote server> is given and its mask doesn't match name of the
parsing server, the CONNECT attempt is sent to the first match of
remote server. Otherwise the CONNECT attempt is made by the server
processing the request.
The server receiving a remote CONNECT command SHOULD generate a
WALLOPS message describing the source and target of the request.
Numeric Replies:
ERR_NOSUCHSERVER ERR_NOPRIVILEGES
ERR_NEEDMOREPARAMS
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Examples:
CONNECT tolsun.oulu.fi 6667 ; Command to attempt to connect local
server to tolsun.oulu.fi on port 6667
3.4.8 Trace message
Command: TRACE
Parameters: [ <target> ]
TRACE command is used to find the route to specific server and
information about its peers. Each server that processes this command
MUST report to the sender about it. The replies from pass-through
links form a chain, which shows route to destination. After sending
this reply back, the query MUST be sent to the next server until
given <target> server is reached.
TRACE command is used to find the route to specific server. Each
server that processes this message MUST tell the sender about it by
sending a reply indicating it is a pass-through link, forming a chain
of replies. After sending this reply back, it MUST then send the
TRACE message to the next server until given server is reached. If
the <target> parameter is omitted, it is RECOMMENDED that TRACE
command sends a message to the sender telling which servers the local
server has direct connection to.
If the destination given by <target> is an actual server, the
destination server is REQUIRED to report all servers, services and
operators which are connected to it; if the command was issued by an
operator, the server MAY also report all users which are connected to
it. If the destination given by <target> is a nickname, then only a
reply for that nickname is given. If the <target> parameter is
omitted, it is RECOMMENDED that the TRACE command is parsed as
targeted to the processing server.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NOSUCHSERVER
If the TRACE message is destined for another server, all
intermediate servers must return a RPL_TRACELINK reply to indicate
that the TRACE passed through it and where it is going next.
RPL_TRACELINK
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A TRACE reply may be composed of any number of the following
numeric replies.
RPL_TRACECONNECTING RPL_TRACEHANDSHAKE
RPL_TRACEUNKNOWN RPL_TRACEOPERATOR
RPL_TRACEUSER RPL_TRACESERVER
RPL_TRACESERVICE RPL_TRACENEWTYPE
RPL_TRACECLASS RPL_TRACELOG
RPL_TRACEEND
Examples:
TRACE *.oulu.fi ; TRACE to a server matching
*.oulu.fi
3.4.9 Admin command
Command: ADMIN
Parameters: [ <target> ]
The admin command is used to find information about the administrator
of the given server, or current server if <target> parameter is
omitted. Each server MUST have the ability to forward ADMIN messages
to other servers.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NOSUCHSERVER
RPL_ADMINME RPL_ADMINLOC1
RPL_ADMINLOC2 RPL_ADMINEMAIL
Examples:
ADMIN tolsun.oulu.fi ; request an ADMIN reply from
tolsun.oulu.fi
ADMIN syrk ; ADMIN request for the server to
which the user syrk is connected
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3.4.10 Info command
Command: INFO
Parameters: [ <target> ]
The INFO command is REQUIRED to return information describing the
server: its version, when it was compiled, the patchlevel, when it
was started, and any other miscellaneous information which may be
considered to be relevant.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NOSUCHSERVER
RPL_INFO RPL_ENDOFINFO
Examples:
INFO csd.bu.edu ; request an INFO reply from
csd.bu.edu
INFO Angel ; request info from the server that
Angel is connected to.
3.5 Service Query and Commands
The service query group of commands has been designed to return
information about any service which is connected to the network.
3.5.1 Servlist message
Command: SERVLIST
Parameters: [ <mask> [ <type> ] ]
The SERVLIST command is used to list services currently connected to
the network and visible to the user issuing the command. The
optional parameters may be used to restrict the result of the query
(to matching services names, and services type).
Numeric Replies:
RPL_SERVLIST RPL_SERVLISTEND
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3.5.2 Squery
Command: SQUERY
Parameters: <servicename> <text>
The SQUERY command is used similarly to PRIVMSG. The only difference
is that the recipient MUST be a service. This is the only way for a
text message to be delivered to a service.
See PRIVMSG for more details on replies and example.
Examples:
SQUERY irchelp :HELP privmsg
; Message to the service with
nickname irchelp.
SQUERY dict@irc.fr :fr2en blaireau
; Message to the service with name
dict@irc.fr.
3.6 User based queries
User queries are a group of commands which are primarily concerned
with finding details on a particular user or group users. When using
wildcards with any of these commands, if they match, they will only
return information on users who are 'visible' to you. The visibility
of a user is determined as a combination of the user's mode and the
common set of channels you are both on.
Although services SHOULD NOT be using this class of message, they are
allowed to.
3.6.1 Who query
Command: WHO
Parameters: [ <mask> [ "o" ] ]
The WHO command is used by a client to generate a query which returns
a list of information which 'matches' the <mask> parameter given by
the client. In the absence of the <mask> parameter, all visible
(users who aren't invisible (user mode +i) and who don't have a
common channel with the requesting client) are listed. The same
result can be achieved by using a <mask> of "0" or any wildcard which
will end up matching every visible user.
The <mask> passed to WHO is matched against users' host, server, real
name and nickname if the channel <mask> cannot be found.
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If the "o" parameter is passed only operators are returned according
to the <mask> supplied.
Numeric Replies:
ERR_NOSUCHSERVER
RPL_WHOREPLY RPL_ENDOFWHO
Examples:
WHO *.fi ; Command to list all users who match
against "*.fi".
WHO jto* o ; Command to list all users with a
match against "jto*" if they are an
operator.
3.6.2 Whois query
Command: WHOIS
Parameters: [ <target> ] <mask> *( "," <mask> )
This command is used to query information about particular user.
The server will answer this command with several numeric messages
indicating different statuses of each user which matches the mask (if
you are entitled to see them). If no wildcard is present in the
<mask>, any information about that nick which you are allowed to see
is presented.
If the <target> parameter is specified, it sends the query to a
specific server. It is useful if you want to know how long the user
in question has been idle as only local server (i.e., the server the
user is directly connected to) knows that information, while
everything else is globally known.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NOSUCHSERVER ERR_NONICKNAMEGIVEN
RPL_WHOISUSER RPL_WHOISCHANNELS
RPL_WHOISCHANNELS RPL_WHOISSERVER
RPL_AWAY RPL_WHOISOPERATOR
RPL_WHOISIDLE ERR_NOSUCHNICK
RPL_ENDOFWHOIS
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Examples:
WHOIS wiz ; return available user information
about nick WiZ
WHOIS eff.org trillian ; ask server eff.org for user
information about trillian
3.6.3 Whowas
Command: WHOWAS
Parameters: <nickname> *( "," <nickname> ) [ <count> [ <target> ] ]
Whowas asks for information about a nickname which no longer exists.
This may either be due to a nickname change or the user leaving IRC.
In response to this query, the server searches through its nickname
history, looking for any nicks which are lexically the same (no wild
card matching here). The history is searched backward, returning the
most recent entry first. If there are multiple entries, up to
<count> replies will be returned (or all of them if no <count>
parameter is given). If a non-positive number is passed as being
<count>, then a full search is done.
Wildcards are allowed in the <target> parameter.
Numeric Replies:
ERR_NONICKNAMEGIVEN ERR_WASNOSUCHNICK
RPL_WHOWASUSER RPL_WHOISSERVER
RPL_ENDOFWHOWAS
Examples:
WHOWAS Wiz ; return all information in the nick
history about nick "WiZ";
WHOWAS Mermaid 9 ; return at most, the 9 most recent
entries in the nick history for
"Mermaid";
WHOWAS Trillian 1 *.edu ; return the most recent history for
"Trillian" from the first server
found to match "*.edu".
3.7 Miscellaneous messages
Messages in this category do not fit into any of the above categories
but are nonetheless still a part of and REQUIRED by the protocol.
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3.7.1 Kill message
Command: KILL
Parameters: <nickname> <comment>
The KILL command is used to cause a client-server connection to be
closed by the server which has the actual connection. Servers
generate KILL messages on nickname collisions. It MAY also be
available available to users who have the operator status.
Clients which have automatic reconnect algorithms effectively make
this command useless since the disconnection is only brief. It does
however break the flow of data and can be used to stop large amounts
of 'flooding' from abusive users or accidents. Abusive users usually
don't care as they will reconnect promptly and resume their abusive
behaviour. To prevent this command from being abused, any user may
elect to receive KILL messages generated for others to keep an 'eye'
on would be trouble spots.
In an arena where nicknames are REQUIRED to be globally unique at all
times, KILL messages are sent whenever 'duplicates' are detected
(that is an attempt to register two users with the same nickname) in
the hope that both of them will disappear and only 1 reappear.
When a client is removed as the result of a KILL message, the server
SHOULD add the nickname to the list of unavailable nicknames in an
attempt to avoid clients to reuse this name immediately which is
usually the pattern of abusive behaviour often leading to useless
"KILL loops". See the "IRC Server Protocol" document [IRC-SERVER]
for more information on this procedure.
The comment given MUST reflect the actual reason for the KILL. For
server-generated KILLs it usually is made up of details concerning
the origins of the two conflicting nicknames. For users it is left
up to them to provide an adequate reason to satisfy others who see
it. To prevent/discourage fake KILLs from being generated to hide
the identify of the KILLer, the comment also shows a 'kill-path'
which is updated by each server it passes through, each prepending
its name to the path.
Numeric Replies:
ERR_NOPRIVILEGES ERR_NEEDMOREPARAMS
ERR_NOSUCHNICK ERR_CANTKILLSERVER
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NOTE:
It is RECOMMENDED that only Operators be allowed to kill other users
with KILL command. This command has been the subject of many
controversies over the years, and along with the above
recommendation, it is also widely recognized that not even operators
should be allowed to kill users on remote servers.
3.7.2 Ping message
Command: PING
Parameters: <server1> [ <server2> ]
The PING command is used to test the presence of an active client or
server at the other end of the connection. Servers send a PING
message at regular intervals if no other activity detected coming
from a connection. If a connection fails to respond to a PING
message within a set amount of time, that connection is closed. A
PING message MAY be sent even if the connection is active.
When a PING message is received, the appropriate PONG message MUST be
sent as reply to <server1> (server which sent the PING message out)
as soon as possible. If the <server2> parameter is specified, it
represents the target of the ping, and the message gets forwarded
there.
Numeric Replies:
ERR_NOORIGIN ERR_NOSUCHSERVER
Examples:
PING tolsun.oulu.fi ; Command to send a PING message to
server
PING WiZ tolsun.oulu.fi ; Command from WiZ to send a PING
message to server "tolsun.oulu.fi"
PING :irc.funet.fi ; Ping message sent by server
"irc.funet.fi"
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3.7.3 Pong message
Command: PONG
Parameters: <server> [ <server2> ]
PONG message is a reply to ping message. If parameter <server2> is
given, this message MUST be forwarded to given target. The <server>
parameter is the name of the entity who has responded to PING message
and generated this message.
Numeric Replies:
ERR_NOORIGIN ERR_NOSUCHSERVER
Example:
PONG csd.bu.edu tolsun.oulu.fi ; PONG message from csd.bu.edu to
tolsun.oulu.fi
3.7.4 Error
Command: ERROR
Parameters: <error message>
The ERROR command is for use by servers when reporting a serious or
fatal error to its peers. It may also be sent from one server to
another but MUST NOT be accepted from any normal unknown clients.
Only an ERROR message SHOULD be used for reporting errors which occur
with a server-to-server link. An ERROR message is sent to the server
at the other end (which reports it to appropriate local users and
logs) and to appropriate local users and logs. It is not to be
passed onto any other servers by a server if it is received from a
server.
The ERROR message is also used before terminating a client
connection.
When a server sends a received ERROR message to its operators, the
message SHOULD be encapsulated inside a NOTICE message, indicating
that the client was not responsible for the error.
Numerics:
None.
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Examples:
ERROR :Server *.fi already exists ; ERROR message to the other server
which caused this error.
NOTICE WiZ :ERROR from csd.bu.edu -- Server *.fi already exists
; Same ERROR message as above but
sent to user WiZ on the other server.
4. Optional features
This section describes OPTIONAL messages. They are not required in a
working server implementation of the protocol described herein. In
the absence of the feature, an error reply message MUST be generated
or an unknown command error. If the message is destined for another
server to answer then it MUST be passed on (elementary parsing
REQUIRED) The allocated numerics for this are listed with the
messages below.
From this section, only the USERHOST and ISON messages are available
to services.
4.1 Away
Command: AWAY
Parameters: [ <text> ]
With the AWAY command, clients can set an automatic reply string for
any PRIVMSG commands directed at them (not to a channel they are on).
The server sends an automatic reply to the client sending the PRIVMSG
command. The only replying server is the one to which the sending
client is connected to.
The AWAY command is used either with one parameter, to set an AWAY
message, or with no parameters, to remove the AWAY message.
Because of its high cost (memory and bandwidth wise), the AWAY
message SHOULD only be used for client-server communication. A
server MAY choose to silently ignore AWAY messages received from
other servers. To update the away status of a client across servers,
the user mode 'a' SHOULD be used instead. (See Section 3.1.5)
Numeric Replies:
RPL_UNAWAY RPL_NOWAWAY
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Example:
AWAY :Gone to lunch. Back in 5 ; Command to set away message to
"Gone to lunch. Back in 5".
4.2 Rehash message
Command: REHASH
Parameters: None
The rehash command is an administrative command which can be used by
an operator to force the server to re-read and process its
configuration file.
Numeric Replies:
RPL_REHASHING ERR_NOPRIVILEGES
Example:
REHASH ; message from user with operator
status to server asking it to reread
its configuration file.
4.3 Die message
Command: DIE
Parameters: None
An operator can use the DIE command to shutdown the server. This
message is optional since it may be viewed as a risk to allow
arbitrary people to connect to a server as an operator and execute
this command.
The DIE command MUST always be fully processed by the server to which
the sending client is connected and MUST NOT be passed onto other
connected servers.
Numeric Replies:
ERR_NOPRIVILEGES
Example:
DIE ; no parameters required.
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4.4 Restart message
Command: RESTART
Parameters: None
An operator can use the restart command to force the server to
restart itself. This message is optional since it may be viewed as a
risk to allow arbitrary people to connect to a server as an operator
and execute this command, causing (at least) a disruption to service.
The RESTART command MUST always be fully processed by the server to
which the sending client is connected and MUST NOT be passed onto
other connected servers.
Numeric Replies:
ERR_NOPRIVILEGES
Example: