This manual is for ERC as distributed with Emacs 28.2.

Copyright © 2005–2022 Free Software Foundation, Inc.

Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual,” and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License”.

(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”

All Emacs Lisp code contained in this document may be used, distributed, and modified without restriction.

Table of Contents

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1 Introduction

ERC is a powerful, modular, and extensible IRC client for Emacs. It is distributed with Emacs since version 22.1.

It comes with the following capabilities enabled by default.

  • Flood control
  • Timestamps
  • Join channels automatically
  • Buttonize URLs, nicknames, and other text
  • Wrap long lines
  • Highlight or remove IRC control characters
  • Highlight pals, fools, and other keywords
  • Detect netsplits
  • Complete nicknames and commands in a programmable fashion
  • Make displayed lines read-only
  • Input history
  • Track channel activity in the mode-line
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    2 Getting Started

    The command M-x erc will start ERC and prompt for the server to connect to.

    If you want to place ERC settings in their own file, you can place them in ~/.emacs.d/.ercrc.el, creating it if necessary.

    If you would rather use the Customize interface to change how ERC works, do M-x customize-group RET erc RET. In particular, ERC comes with lots of modules that may be enabled or disabled; to select which ones you want, do M-x customize-variable RET erc-modules RET.

    2.1 Sample Session

    This is an example ERC session which shows how to connect to the ‘#emacs’ channel on Libera.Chat. Another IRC channel on Libera.Chat that may be of interest is ‘#erc’, which is a channel where ERC users and developers hang out. These channels used to live on the Freenode IRC network until June 2021, when they—along with the official IRC channels of the GNU Project, the Free Software Foundation, and many other free software communities—relocated to the Libera.Chat network in the aftermath of changes in governance and policies of Freenode in May and June 2021. GNU and FSF’s announcements about this are at,, and

    • Connect to Libera.Chat

      Run M-x erc. Use “” as the IRC server, “6667” as the port, and choose a nickname.

    • Get used to the interface

      Switch to the “” buffer, if you’re not already there. You will see first some messages about checking for ident, and then a bunch of other messages that describe the current IRC server.

    • Join the #emacs channel

      In that buffer, type “/join SPC #emacs” and hit RET. Depending on how you’ve set up ERC, either a new buffer for “#emacs” will be displayed, or a new buffer called “#emacs” will be created in the background. If the latter, switch to the “#emacs” buffer. You will see the channel topic and a list of the people who are currently on the channel.

    • Register your nickname with Libera.Chat

      If you would like to be able to talk with people privately on the Libera.Chat network, you will have to “register” your nickname. To do so, switch to the “” buffer and type “/msg NickServ register <password>”, replacing “<password>” with your desired password. It should tell you that the operation was successful.

    • Talk to people in the channel

      If you switch back to the “#emacs” buffer, you can type a message, and everyone on the channel will see it.

    • Open a query buffer to talk to someone

      If you want to talk with someone in private (this should usually not be done for technical help, only for personal questions), type “/query <nick>”, replacing “<nick>” with the nickname of the person you would like to talk to. Depending on how ERC is set up, you will either see a new buffer with the name of the person, or such a buffer will be created in the background and you will have to switch to it. Begin typing messages, and you will be able to have a conversation.

      Note that if the other person is not registered, you will not be able to talk with them.

    2.2 Special Features

    ERC has some features that distinguish it from some IRC clients.

    • multiple channels and multiple servers

      Every channel is put in a separate buffer. Several IRC servers may be connected to at the same time.

    • private message separation

      Private conversations are treated as channels, and are put into separate buffers in Emacs. We call these “query buffers”.

    • highlighting

      Some occurrences of words can be highlighted, which makes it easier to track different kinds of conversations.

    • notification

      ERC can notify you that certain users are online.

    • channel tracking

      Channels can be hidden and conversation continue in the background. You are notified when something is said in such a channel that is not currently visible. This makes it easy to get Real Work done while still maintaining an IRC presence.

    • nick completion

      ERC can complete words upon hitting TAB, which eases the writing of nicknames in messages.

    • history

      Past actions are kept in history rings for future use. To navigate a history ring, hit M-p to go backwards and M-n to go forwards.

    • multiple languages

      Different channels and servers may have different language encodings.

      multiple languages. Please contact the Emacs developers if you are interested in helping with the translation effort.

    • user scripting

      Users can load scripts (e.g., auto greeting scripts) when ERC starts up.

      It is also possible to make custom IRC commands, if you know a little Emacs Lisp. Just make an Emacs Lisp function and call it erc-cmd-NEWCOMMAND, where NEWCOMMAND is the name of the new command in capital letters.

    • auto reconnect

      If the connection goes away at some point, ERC will try to reconnect automatically. If it fails to reconnect, and you want to try to manually reestablish the connection at some later point, switch to an ERC buffer and run the /RECONNECT command.

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    3 Keys Used in ERC

    This is a summary of keystrokes available in every ERC buffer.

    C-a or <home> (erc-bol)

    Go to beginning of line or end of prompt.

    RET (erc-send-current-line)

    Send the current line

    TAB (completion-at-point or erc-button-next)

    If at prompt, complete the current word. Otherwise, move to the next link or button.

    M-TAB (ispell-complete-word)

    Complete the given word, using ispell.

    C-c C-a (erc-bol)

    Go to beginning of line or end of prompt.

    C-c C-b (erc-switch-to-buffer)

    Use read-buffer to prompt for a ERC buffer to switch to.

    C-c C-c (erc-toggle-interpret-controls)

    Toggle interpretation of control sequences in messages.

    C-c C-d (erc-input-action)

    Interactively input a user action and send it to IRC.

    C-c C-e (erc-toggle-ctcp-autoresponse)

    Toggle automatic CTCP replies (like VERSION and PING).

    C-c C-f (erc-toggle-flood-control)

    Toggle use of flood control on sent messages.

    C-c TAB (erc-invite-only-mode)

    Turn on the invite only mode (+i) for the current channel.

    C-c C-j (erc-join-channel)

    Join channel. If point is at the beginning of a channel name, use that as default.

    C-c C-k (erc-go-to-log-matches-buffer)

    Interactively open an erc-log-matches buffer

    C-c C-l (erc-save-buffer-in-logs)

    Append buffer contents to the log file, if logging is enabled.

    C-c C-n (erc-channel-names)

    Run "/names #channel" in the current channel.

    C-c C-o (erc-get-channel-mode-from-keypress)

    Read a key sequence and call the corresponding channel mode function. After doing C-c C-o, type in a channel mode letter.

    C-g means quit. RET lets you type more than one mode at a time. If l is pressed, erc-set-channel-limit gets called. If k is pressed, erc-set-channel-key gets called. Anything else will be sent to erc-toggle-channel-mode.

    C-c C-p (erc-part-from-channel)

    Part from the current channel and prompt for a reason.

    C-c C-q (erc-quit-server)

    Disconnect from current server after prompting for reason.

    C-c C-r (erc-remove-text-properties-region)

    Clears the region (start,end) in object from all colors, etc.

    C-c C-t (erc-set-topic)

    Prompt for a topic for the current channel.

    C-c C-u (erc-kill-input)

    Kill current input line using erc-bol followed by kill-line.

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    4 Modules

    One way to add functionality to ERC is to customize which of its many modules are loaded.

    There is a spiffy customize interface, which may be reached by typing M-x customize-option RET erc-modules RET. Alternatively, set erc-modules manually and then call erc-update-modules.

    The following is a list of available modules.


    Set away status automatically


    Join channels automatically


    Integrate with the Big Brother Database


    Buttonize URLs, nicknames, and other text


    Mark unidentified users on freenode and other servers supporting CAPAB.

    completion (aka pcomplete)

    Complete nicknames and commands (programmable)


    Wrap long lines


    Launch an identd server on port 8113


    Highlight or remove IRC control characters


    Save buffers in logs


    Highlight pals, fools, and other keywords


    Display a menu in ERC buffers


    Detect netsplits


    Don’t display non-IRC commands after evaluation


    Notify when the online status of certain users changes


    Send you a notification when you get a private message, or your nickname is mentioned


    Process CTCP PAGE requests from IRC


    Make displayed lines read-only


    Replace text in messages


    Enable an input history


    Scroll to the bottom of the buffer


    Identify to Nickserv (IRC Services) automatically


    Convert smileys to pretty icons


    Play sounds when you receive CTCP SOUND requests


    Check spelling of messages


    Add timestamps to messages


    Track channel activity in the mode-line


    Truncate buffers to a certain size


    Translate morse code in messages

    5 Advanced Usage

    5.1 Connecting to an IRC Server

    The easiest way to connect to an IRC server is to call M-x erc. If you want to assign this function to a keystroke, the following will help you figure out its parameters.

    Function: erc

    Select connection parameters and run ERC. Non-interactively, it takes the following keyword arguments.

    • server
    • port
    • nick
    • password
    • full-name

    That is, if called with the following arguments, server and full-name will be set to those values, whereas erc-compute-port and erc-compute-nick will be invoked for the values of the other parameters.

    (erc :server "" :full-name "J. Random Hacker")

    To connect securely over an encrypted TLS connection, use M-x erc-tls.

    Function: erc-tls

    Select connection parameters and run ERC over TLS. Non-interactively, it takes the following keyword arguments.

    • server
    • port
    • nick
    • password
    • full-name
    • client-certificate

    That is, if called with the following arguments, server and full-name will be set to those values, whereas erc-compute-port and erc-compute-nick will be invoked for the values of the other parameters, and client-certificate will be nil.

    (erc-tls :server "" :full-name "J. Random Hacker")

    To use a certificate with erc-tls, specify the optional client-certificate keyword argument, whose value should be as described in the documentation of open-network-stream: if non-nil, it should either be a list where the first element is the file name of the private key corresponding to a client certificate and the second element is the file name of the client certificate itself to use when connecting over TLS, or t, which means that auth-source will be queried for the private key and the certificate. Authenticating using a TLS client certificate is also referred to as “CertFP” (Certificate Fingerprint) authentication by various IRC networks.

    Examples of use:

    (erc-tls :server "" :port 6697
    (erc-tls :server "" :port 6697
             `(,(expand-file-name "~/cert-libera.key")
               ,(expand-file-name "~/cert-libera.crt")))
    (erc-tls :server "" :port 6697
             :client-certificate t)

    In the case of :client-certificate t, you will need to add a line like the following to your authinfo file (e.g. ~/.authinfo.gpg):

    machine key /home/bandali/my-cert.key cert /home/bandali/my-cert.crt

    See Help for users in Emacs auth-source Library, for more on the .authinfo/.netrc backend of auth-source.


    Function: erc-compute-server &optional server

    Return an IRC server name.

    This tries a number of increasingly more default methods until a non-nil value is found.

    • server (the argument passed to this function)
    • The erc-server option
    • The value of the IRCSERVER environment variable
    • The erc-default-server variable
    User Option: erc-server

    IRC server to use if one is not provided.


    Function: erc-compute-port &optional port

    Return a port for an IRC server.

    This tries a number of increasingly more default methods until a non-nil value is found.

    • port (the argument passed to this function)
    • The erc-port option
    • The erc-default-port variable
    User Option: erc-port

    IRC port to use if not specified.

    This can be either a string or a number.


    Function: erc-compute-nick &optional nick

    Return user’s IRC nick.

    This tries a number of increasingly more default methods until a non-nil value is found.

    • nick (the argument passed to this function)
    • The erc-nick option
    • The value of the IRCNICK environment variable
    • The result from the user-login-name function
    User Option: erc-nick

    Nickname to use if one is not provided.

    This can be either a string, or a list of strings. In the latter case, if the first nick in the list is already in use, other nicks are tried in the list order.

    User Option: erc-format-nick-function

    A function to format a nickname for message display

    You can set this to erc-format-@nick to display user mode prefix

    (setq erc-format-nick-function 'erc-format-@nick)
    User Option: erc-nick-uniquifier

    The string to append to the nick if it is already in use.

    User Option: erc-try-new-nick-p

    If the nickname you chose isn’t available, and this option is non-nil, ERC should automatically attempt to connect with another nickname.

    You can manually set another nickname with the /NICK command.


    User Option: erc-prompt-for-password

    If non-nil (the default), M-x erc prompts for a password.

    If you prefer, you can set this option to nil and use the auth-source mechanism to store your password. For instance, if you use ~/.authinfo as your auth-source backend, then put something like the following in that file:

    machine login "#fsf" password sEcReT

    ERC also consults auth-source to find any channel keys required for the channels that you wish to autojoin, as specified by the variable erc-autojoin-channels-alist.

    For more details, see auth-source in Emacs auth-source Library.

    Full name

    Function: erc-compute-full-name &optional full-name

    Return user’s full name.

    This tries a number of increasingly more default methods until a non-nil value is found.

    • full-name (the argument passed to this function)
    • The erc-user-full-name option
    • The value of the IRCNAME environment variable
    • The result from the user-full-name function
    User Option: erc-user-full-name

    User full name.

    This can be either a string or a function to call.

    5.2 Sample Configuration

    Here is an example of configuration settings for ERC. This can go into your Emacs configuration file. Everything after the (require 'erc) command can optionally go into ~/.emacs.d/.ercrc.el.

    ;;; Sample ERC configuration
    ;; Load authentication info from an external source.  Put sensitive
    ;; passwords and the like in here.
    (load "~/.emacs.d/.erc-auth")
    ;; This is an example of how to make a new command.  Type "/uptime" to
    ;; use it.
    (defun erc-cmd-UPTIME (&rest ignore)
      "Display the uptime of the system, as well as some load-related
    stuff, to the current ERC buffer."
      (let ((uname-output
              ", load average: " "] {Load average} ["
              ;; Collapse spaces, remove
               " +" " "
               ;; Remove beginning and trailing whitespace
                "^ +\\|[ \n]+$" ""
                (shell-command-to-string "uptime"))))))
         (concat "{Uptime} [" uname-output "]"))))
    ;; This causes ERC to connect to the Libera.Chat network upon hitting
    ;; C-c e f.  Replace MYNICK with your IRC nick.
    (global-set-key "\C-cef" (lambda () (interactive)
                               (erc :server "" :port "6667"
                                    :nick "MYNICK")))
    ;; This causes ERC to connect to the IRC server on your own machine (if
    ;; you have one) upon hitting C-c e b.  Replace MYNICK with your IRC
    ;; nick.  Often, people like to run bitlbee ( as an
    ;; AIM/Jabber/MSN to IRC gateway, so that they can use ERC to chat with
    ;; people on those networks.
    (global-set-key "\C-ceb" (lambda () (interactive)
                               (erc :server "localhost" :port "6667"
                                    :nick "MYNICK")))
    ;; Make C-c RET (or C-c C-RET) send messages instead of RET.  This has
    ;; been commented out to avoid confusing new users.
    ;; (define-key erc-mode-map (kbd "RET") nil)
    ;; (define-key erc-mode-map (kbd "C-c RET") 'erc-send-current-line)
    ;; (define-key erc-mode-map (kbd "C-c C-RET") 'erc-send-current-line)
    ;;; Options
    ;; Join the #emacs and #erc channels whenever connecting to
    ;; Libera.Chat.
    (setq erc-autojoin-channels-alist
          '(("Libera.Chat" "#emacs" "#erc")))
    ;; Rename server buffers to reflect the current network name instead
    ;; of SERVER:PORT (e.g., "Libera.Chat" instead of
    ;; "").  This is useful when using a bouncer like
    ;; ZNC where you have multiple connections to the same server.
    (setq erc-rename-buffers t)
    ;; Interpret mIRC-style color commands in IRC chats
    (setq erc-interpret-mirc-color t)
    ;; The following are commented out by default, but users of other
    ;; non-Emacs IRC clients might find them useful.
    ;; Kill buffers for channels after /part
    ;; (setq erc-kill-buffer-on-part t)
    ;; Kill buffers for private queries after quitting the server
    ;; (setq erc-kill-queries-on-quit t)
    ;; Kill buffers for server messages after quitting the server
    ;; (setq erc-kill-server-buffer-on-quit t)

    5.3 Options

    This section is extremely incomplete. For now, the easiest way to check out all the available options for ERC is to do M-x customize-group RET erc RET.

    User Option: erc-hide-list

    If non, nil, this is a list of IRC message types to hide, e.g.:

    (setq erc-hide-list '("JOIN" "PART" "QUIT"))
    User Option: erc-network-hide-list

    If non, nil, this is a list of IRC networks and message types to hide, e.g.:

    (setq erc-network-hide-list (("Libera.Chat" "JOIN" "PART" "QUIT")
    ("OFTC" "JOIN" "PART""))
    User Option: erc-channel-hide-list

    If non, nil, this is a list of IRC channels and message types to hide, e.g.:

    (setq erc-channel-hide-list (("#erc" "JOIN" "PART" "QUIT")
    ("#emacs" "NICK"))
    User Option: erc-lurker-hide-list

    Like erc-hide-list, but only applies to messages sent by lurkers. The function erc-lurker-p determines whether a given nickname is considered a lurker.

    User Option: erc-rename-buffers

    If non, nil, this will rename server buffers to reflect the current network name instead of IP:PORT

    (setq erc-rename-buffers t)

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    6 Getting Help and Reporting Bugs

    After you have read this guide, if you still have questions about ERC, or if you have bugs to report, there are several places you can go.

    7 History

    ERC was originally written by Alexander L. Belikoff and Sergey Berezin. They stopped development around December 1999. Their last released version was ERC 2.0.

    P.S.: If one of the original developers of ERC reads this, we’d like to receive additional information for this file and hear comments in general.

    • 2001

      In June 2001, Mario Lang and Alex Schroeder took over development and created a ERC Project at

      In reaction to a mail about the new ERC development effort, Sergey Berezin said, “First of all, I’m glad that my version of ERC is being used out there. The thing is, I do not have free time and enough incentive anymore to work on ERC, so I would be happy if you guys take over the project entirely.”

      So we happily hacked away on ERC, and soon after (September 2001) released the next "stable" version, 2.1.

      Most of the development of the new ERC happened on ‘#emacs’ on Over time, many people contributed code, ideas, bugfixes, and a lot of alpha/beta/gamma testing.

      See the CREDITS file for a list of contributors.

    • 2003

      ERC 3.0 was released.

    • 2004

      ERC 4.0 was released.

    • 2005

      ERC 5.0 was released. Michael Olson became the release manager and eventually the maintainer.

      After some discussion between him and the Emacs developers, it was decided to include ERC in Emacs.

    • 2006

      ERC 5.1 was released. It was subsequently included in Emacs 22.

      ERC became an official GNU project, and development moved to We switched to using GNU Arch as our revision control system. Our mailing list address changed as well.

    • 2007

      We switched to using git for our version control system.

    • 2009+

      Since about 2009, ERC is no longer developed as a separate project, but is maintained as part of Emacs.

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    Appendix A GNU Free Documentation License

    Version 1.3, 3 November 2008
    Copyright © 2000, 2001, 2002, 2007, 2008 Free Software Foundation, Inc.
    Everyone is permitted to copy and distribute verbatim copies
    of this license document, but changing it is not allowed.

      The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.

      This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.

      We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.


      This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.

      A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.

      A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.

      The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.

      The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.

      A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.

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      The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.


      You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.

      You may also lend copies, under the same conditions stated above, and you may publicly display copies.


      If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.

      If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.

      If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.

      It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.


      You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:

      1. Use in the Title Page (and on the covers, if any) a title distinct from that of the Document, and from those of previous versions (which should, if there were any, be listed in the History section of the Document). You may use the same title as a previous version if the original publisher of that version gives permission.
      2. List on the Title Page, as authors, one or more persons or entities responsible for authorship of the modifications in the Modified Version, together with at least five of the principal authors of the Document (all of its principal authors, if it has fewer than five), unless they release you from this requirement.
      3. State on the Title page the name of the publisher of the Modified Version, as the publisher.
      4. Preserve all the copyright notices of the Document.
      5. Add an appropriate copyright notice for your modifications adjacent to the other copyright notices.
      6. Include, immediately after the copyright notices, a license notice giving the public permission to use the Modified Version under the terms of this License, in the form shown in the Addendum below.
      7. Preserve in that license notice the full lists of Invariant Sections and required Cover Texts given in the Document’s license notice.
      8. Include an unaltered copy of this License.
      9. Preserve the section Entitled “History”, Preserve its Title, and add to it an item stating at least the title, year, new authors, and publisher of the Modified Version as given on the Title Page. If there is no section Entitled “History” in the Document, create one stating the title, year, authors, and publisher of the Document as given on its Title Page, then add an item describing the Modified Version as stated in the previous sentence.
      10. Preserve the network location, if any, given in the Document for public access to a Transparent copy of the Document, and likewise the network locations given in the Document for previous versions it was based on. These may be placed in the “History” section. You may omit a network location for a work that was published at least four years before the Document itself, or if the original publisher of the version it refers to gives permission.
      11. For any section Entitled “Acknowledgements” or “Dedications”, Preserve the Title of the section, and preserve in the section all the substance and tone of each of the contributor acknowledgements and/or dedications given therein.
      12. Preserve all the Invariant Sections of the Document, unaltered in their text and in their titles. Section numbers or the equivalent are not considered part of the section titles.
      13. Delete any section Entitled “Endorsements”. Such a section may not be included in the Modified Version.
      14. Do not retitle any existing section to be Entitled “Endorsements” or to conflict in title with any Invariant Section.
      15. Preserve any Warranty Disclaimers.

      If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.

      You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.

      You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.

      The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.


      You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.

      The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.

      In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”


      You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.

      You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.


      A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.

      If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.


      Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.

      If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.


      You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.

      However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.

      Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.

      Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.


      The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See

      Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.


      “Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.

      “CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.

      “Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.

      An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.

      The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.

    ADDENDUM: How to use this License for your documents

    To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:

      Copyright (C)  year  your name.
      Permission is granted to copy, distribute and/or modify this document
      under the terms of the GNU Free Documentation License, Version 1.3
      or any later version published by the Free Software Foundation;
      with no Invariant Sections, no Front-Cover Texts, and no Back-Cover
      Texts.  A copy of the license is included in the section entitled ``GNU
      Free Documentation License''.

    If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:

        with the Invariant Sections being list their titles, with
        the Front-Cover Texts being list, and with the Back-Cover Texts
        being list.

    If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.

    If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.


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    Index Entry  Section

    advanced topics: Advanced Usage

    bugs, reporting: Getting Help and Reporting Bugs

    configuration, sample: Sample Configuration
    connecting: Connecting

    erc: Connecting
    erc-compute-full-name: Connecting
    erc-compute-nick: Connecting
    erc-compute-port: Connecting
    erc-compute-server: Connecting
    erc-tls: Connecting

    help, getting: Getting Help and Reporting Bugs
    history ring: Special Features
    history, of ERC: History

    keystrokes: Keystroke Summary

    modules: Modules
    modules, autoaway: Modules
    modules, autojoin: Modules
    modules, bbdb: Modules
    modules, button: Modules
    modules, capab-identify: Modules
    modules, completion: Modules
    modules, fill: Modules
    modules, identd: Modules
    modules, irccontrols: Modules
    modules, log: Modules
    modules, match: Modules
    modules, menu: Modules
    modules, netsplit: Modules
    modules, noncommands: Modules
    modules, notifications: Modules
    modules, notify: Modules
    modules, page: Modules
    modules, pcomplete: Modules
    modules, readonly: Modules
    modules, replace: Modules
    modules, ring: Modules
    modules, scrolltobottom: Modules
    modules, services: Modules
    modules, smiley: Modules
    modules, sound: Modules
    modules, spelling: Modules
    modules, stamp: Modules
    modules, track: Modules
    modules, truncate: Modules
    modules, unmorse: Modules

    options: Options

    password: Connecting

    query buffers: Special Features

    settings: Getting Started

    Jump to:   A   B   C   E   H   K   M   O   P   Q   S