doc/misc/erc.texi

\input texinfo
@c %**start of header
@setfilename ../../info/erc.info
@settitle ERC Manual
@include docstyle.texi
@syncodeindex fn cp
@include emacsver.texi
@c %**end of header

@copying
This manual is for ERC as distributed with Emacs @value{EMACSVER}.

Copyright @copyright{} 2005--2021 Free Software Foundation, Inc.

@quotation
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.
@end quotation
@end copying

@dircategory Emacs network features
@direntry
* ERC: (erc).                   Powerful and extensible IRC client for Emacs.
@end direntry

@titlepage
@title ERC manual
@subtitle a full-featured IRC client
@subtitle for Emacs

@c The following two commands
@c start the copyright page.
@page
@vskip 0pt plus 1filll
@insertcopying
@end titlepage

@contents

@ifnottex
@node Top
@top ERC

@insertcopying
@end ifnottex

@menu
* Introduction::                What is ERC?
* Getting Started::             Quick Start guide to using ERC.
* Keystroke Summary::           Keystrokes used in ERC buffers.
* Modules::                     Available modules for ERC.
* Advanced Usage::              Cool ways of using ERC.
* Getting Help and Reporting Bugs::
* History::                     The history of ERC.
* GNU Free Documentation License::  The license for this documentation.
* Concept Index::               Search for terms.

@detailmenu
 --- The Detailed Node Listing ---

Getting Started

* Sample Session::              Example of connecting to the #emacs channel
* Special Features::            Differences from standalone IRC clients

Advanced Usage

* Connecting::                  Ways of connecting to an IRC server.
* Sample Configuration::        An example configuration file.
* Options::                     Options that are available for ERC.

@end detailmenu
@end menu

@node Introduction
@chapter 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.

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

@end itemize


@node Getting Started
@chapter Getting Started
@cindex settings

The command @kbd{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 @file{~/.emacs.d/.ercrc.el}, creating it if necessary.

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

@menu
* Sample Session::              Example of connecting to the #emacs channel
* Special Features::            Differences from standalone IRC clients
@end menu

@node Sample Session
@section Sample Session

This is an example ERC session which shows how to connect to the #emacs
channel on Freenode.  Another IRC channel on Freenode that may be of
interest is #erc, which is a channel where ERC users and developers hang
out.

@itemize @bullet

@item Connect to Freenode

Run @kbd{M-x erc}.  Use ``irc.freenode.net'' as the IRC server, ``6667''
as the port, and choose a nickname.

@item Get used to the interface

Switch to the ``irc.freenode.net:6667'' 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.

@item Join the #emacs channel

In that buffer, type ``/join @key{SPC} #emacs'' and hit @kbd{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.

@item Register your nickname with Freenode

If you would like to be able to talk with people privately on the
Freenode network, you will have to ``register'' your nickname.  To do
so, switch to the ``irc.freenode.net:6667'' buffer and type ``/msg
NickServ register <password>'', replacing ``<password>'' with your
desired password.  It should tell you that the operation was successful.

@item 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.

@item 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.

@end itemize

@node Special Features
@section Special Features

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

@itemize @bullet

@item multiple channels and multiple servers

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

@cindex query buffers
@item private message separation

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

@item highlighting

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

@item notification

ERC can notify you that certain users are online.

@item 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.

@item nick completion

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

@cindex history ring
@item history

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

@item 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.

@item 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
@code{erc-cmd-NEWCOMMAND}, where @code{NEWCOMMAND} is the name of the
new command in capital letters.

@item 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 @code{/RECONNECT} command.

@end itemize


@node Keystroke Summary
@chapter Keys Used in ERC
@cindex keystrokes

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

@table @kbd

@item C-a or <home> (@code{erc-bol})
Go to beginning of line or end of prompt.

@item @key{RET} (@code{erc-send-current-line})
Send the current line

@item @key{TAB} (@code{erc-complete-word})
If at prompt, complete the current word.
Otherwise, move to the next link or button.

@item M-@key{TAB} (@code{ispell-complete-word})
Complete the given word, using ispell.

@item C-c C-a (@code{erc-bol})
Go to beginning of line or end of prompt.

@item C-c C-b (@code{erc-switch-to-buffer})
Use @code{read-buffer} to prompt for a ERC buffer to switch to.

@item C-c C-c (@code{erc-toggle-interpret-controls})
Toggle interpretation of control sequences in messages.

@item C-c C-d (@code{erc-input-action})
Interactively input a user action and send it to IRC.

@item C-c C-e (@code{erc-toggle-ctcp-autoresponse})
Toggle automatic CTCP replies (like VERSION and PING).

@item C-c C-f (@code{erc-toggle-flood-control})
Toggle use of flood control on sent messages.

@item C-c @key{TAB} (@code{erc-invite-only-mode})
Turn on the invite only mode (+i) for the current channel.

@item C-c C-j (@code{erc-join-channel})
Join channel.  If point is at the beginning of a channel name, use that
as default.

@item C-c C-k (@code{erc-go-to-log-matches-buffer})
Interactively open an erc-log-matches buffer

@item C-c C-l (@code{erc-save-buffer-in-logs})
Append buffer contents to the log file, if logging is enabled.

@item C-c C-n (@code{erc-channel-names})
Run "/names #channel" in the current channel.

@item C-c C-o (@code{erc-get-channel-mode-from-keypress})
Read a key sequence and call the corresponding channel mode function.
After doing @kbd{C-c C-o}, type in a channel mode letter.

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

@item C-c C-p (@code{erc-part-from-channel})
Part from the current channel and prompt for a reason.

@item C-c C-q (@code{erc-quit-server})
Disconnect from current server after prompting for reason.

@item C-c C-r (@code{erc-remove-text-properties-region})
Clears the region (start,end) in object from all colors, etc.

@item C-c C-t (@code{erc-set-topic})
Prompt for a topic for the current channel.

@item C-c C-u (@code{erc-kill-input})
Kill current input line using @code{erc-bol} followed by @code{kill-line}.

@end table


@node Modules
@chapter Modules
@cindex 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
@kbd{M-x customize-option @key{RET} erc-modules @key{RET}}.
Alternatively, set @code{erc-modules} manually and then call
@code{erc-update-modules}.

The following is a list of available modules.

@table @code

@cindex modules, autoaway
@item autoaway
Set away status automatically

@cindex modules, autojoin
@item autojoin
Join channels automatically

@cindex modules, bbdb
@item bbdb
Integrate with the Big Brother Database

@cindex modules, button
@item button
Buttonize URLs, nicknames, and other text

@cindex modules, capab-identify
@item capab-identify
Mark unidentified users on freenode and other servers supporting CAPAB.

@cindex modules, completion
@cindex modules, pcomplete
@item completion (aka pcomplete)
Complete nicknames and commands (programmable)

@cindex modules, fill
@item fill
Wrap long lines

@cindex modules, identd
@item identd
Launch an identd server on port 8113

@cindex modules, irccontrols
@item irccontrols
Highlight or remove IRC control characters

@cindex modules, log
@item log
Save buffers in logs

@cindex modules, match
@item match
Highlight pals, fools, and other keywords

@cindex modules, menu
@item menu
Display a menu in ERC buffers

@cindex modules, netsplit
@item netsplit
Detect netsplits

@cindex modules, noncommands
@item noncommands
Don't display non-IRC commands after evaluation

@cindex modules, notify
@item notify
Notify when the online status of certain users changes

@cindex modules, notifications
@item notifications
Send you a notification when you get a private message,
or your nickname is mentioned

@cindex modules, page
@item page
Process CTCP PAGE requests from IRC

@cindex modules, readonly
@item readonly
Make displayed lines read-only

@cindex modules, replace
@item replace
Replace text in messages

@cindex modules, ring
@item ring
Enable an input history

@cindex modules, scrolltobottom
@item scrolltobottom
Scroll to the bottom of the buffer

@cindex modules, services
@item services
Identify to Nickserv (IRC Services) automatically

@cindex modules, smiley
@item smiley
Convert smileys to pretty icons

@cindex modules, sound
@item sound
Play sounds when you receive CTCP SOUND requests

@cindex modules, spelling
@item spelling
Check spelling of messages

@cindex modules, stamp
@item stamp
Add timestamps to messages

@cindex modules, track
@item track
Track channel activity in the mode-line

@cindex modules, truncate
@item truncate
Truncate buffers to a certain size

@cindex modules, unmorse
@item unmorse
Translate morse code in messages

@end table

@c PRE5_4: Document every option of every module in its own subnode


@node Advanced Usage
@chapter Advanced Usage
@cindex advanced topics

@menu
* Connecting::                  Ways of connecting to an IRC server.
* Sample Configuration::        An example configuration file.
* Options::                     Options that are available for ERC.
@end menu

@node Connecting
@section Connecting to an IRC Server
@cindex connecting

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

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

@itemize @bullet
@item @var{server}
@item @var{port}
@item @var{nick}
@item @var{password}
@item @var{full-name}
@end itemize

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

@example
(erc :server "irc.freenode.net" :full-name "Harry S Truman")
@end example
@end defun

@subheading Server

@defun erc-compute-server &optional server
Return an IRC server name.

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

@itemize @bullet
@item @var{server} (the argument passed to this function)
@item The @code{erc-server} option
@item The value of the IRCSERVER environment variable
@item The @code{erc-default-server} variable
@end itemize

@end defun

@defopt erc-server
IRC server to use if one is not provided.
@end defopt

@subheading Port

@defun erc-compute-port &optional port
Return a port for an IRC server.

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

@itemize @bullet
@item @var{port} (the argument passed to this function)
@item The @code{erc-port} option
@item The @code{erc-default-port} variable
@end itemize

@end defun

@defopt erc-port
IRC port to use if not specified.

This can be either a string or a number.
@end defopt

@subheading Nick

@defun erc-compute-nick &optional nick
Return user's IRC nick.

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

@itemize
@item @var{nick} (the argument passed to this function)
@item The @code{erc-nick} option
@item The value of the IRCNICK environment variable
@item The result from the @code{user-login-name} function
@end itemize

@end defun

@defopt 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.
@end defopt

@defopt erc-format-nick-function
A function to format a nickname for message display

You can set this to @code{erc-format-@@nick} to display user mode prefix
@end defopt

@example
(setq erc-format-nick-function 'erc-format-@@nick)
@end example

@defopt erc-nick-uniquifier
The string to append to the nick if it is already in use.
@end defopt

@defopt erc-try-new-nick-p
If the nickname you chose isn't available, and this option is non-@code{nil},
ERC should automatically attempt to connect with another nickname.

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

@subheading Password
@cindex password

@defopt erc-prompt-for-password
If non-@code{nil} (the default), @kbd{M-x erc} prompts for a password.
@end defopt

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

@example
machine irc.example.net login "#fsf" password sEcReT
@end example

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

For more details, @pxref{Top,,auth-source, auth, Emacs auth-source Library}.


@subheading Full name

@defun erc-compute-full-name &optional full-name
Return user's full name.

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

@itemize @bullet
@item @var{full-name} (the argument passed to this function)
@item The @code{erc-user-full-name} option
@item The value of the IRCNAME environment variable
@item The result from the @code{user-full-name} function
@end itemize

@end defun

@defopt erc-user-full-name
User full name.

This can be either a string or a function to call.
@end defopt

@node Sample Configuration
@section Sample Configuration
@cindex configuration, sample

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

@lisp
;;; 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
         (replace-regexp-in-string
          ", load average: " "] @{Load average@} ["
          ;; Collapse spaces, remove
          (replace-regexp-in-string
           " +" " "
           ;; Remove beginning and trailing whitespace
           (replace-regexp-in-string
            "^ +\\|[ \n]+$" ""
            (shell-command-to-string "uptime"))))))
    (erc-send-message
     (concat "@{Uptime@} [" uname-output "]"))))

;; This causes ERC to connect to the Freenode network upon hitting
;; C-c e f.  Replace MYNICK with your IRC nick.
(global-set-key "\C-cef" (lambda () (interactive)
                           (erc :server "irc.freenode.net" :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 (https://bitlbee.org/) 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 Freenode.
(setq erc-autojoin-channels-alist '(("freenode.net" "#emacs" "#erc")))

;; Rename server buffers to reflect the current network name instead
;; of SERVER:PORT (e.g., "freenode" instead of "irc.freenode.net:6667").
;; 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)
@end lisp

@node Options
@section Options
@cindex options

@c PRE5_4: (Node) Document every ERC option (module options go in
@c previous chapter)

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

@defopt erc-hide-list
If non, @code{nil}, this is a list of IRC message types to hide, e.g.:

@example
(setq erc-hide-list '("JOIN" "PART" "QUIT"))
@end example
@end defopt

@defopt erc-network-hide-list
If non, @code{nil}, this is a list of IRC networks and message types
to hide, e.g.:

@example
(setq erc-network-hide-list (("freenode" "JOIN" "PART" "QUIT")
("OFTC" "JOIN" "PART""))
@end example
@end defopt

@defopt erc-channel-hide-list
If non, @code{nil}, this is a list of IRC channels and message types
to hide, e.g.:

@example
(setq erc-channel-hide-list (("#erc" "JOIN" "PART" "QUIT")
("#emacs" "NICK"))
@end example
@end defopt

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

@defopt erc-rename-buffers
If non, @code{nil}, this will rename server buffers to reflect the
current network name instead of IP:PORT

@example
(setq erc-rename-buffers t)
@end example
@end defopt

@node Getting Help and Reporting Bugs
@chapter Getting Help and Reporting Bugs
@cindex help, getting
@cindex bugs, reporting

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.

@itemize @bullet

@item
@uref{https://www.emacswiki.org/emacs/ERC} is the
emacswiki.org page for ERC@.  Anyone may add tips, hints, etc.@: to it.

@item
You can ask questions about using ERC on the Emacs mailing list,
@uref{https://lists.gnu.org/mailman/listinfo/help-gnu-emacs}.

@item
You can visit the IRC Freenode channel @samp{#emacs}. Many of the
contributors are frequently around and willing to answer your
questions.

@item
To report a bug in ERC, use @kbd{M-x report-emacs-bug}.

@end itemize


@node History
@chapter History
@cindex history, of ERC

@c abel@@bfr.co.il, sergey.berezin@@cs.cmu.edu
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.

@itemize
@item 2001

@c mlang@@delysid.org, alex@@gnu.org
In June 2001, Mario Lang and Alex Schroeder
took over development and created a ERC Project at
@uref{https://sourceforge.net/projects/erc}.

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
irc.openprojects.net.  Over time, many people contributed code, ideas,
bugfixes, and a lot of alpha/beta/gamma testing.

See the @file{CREDITS} file for a list of contributors.

@item 2003

ERC 3.0 was released.

@item 2004

ERC 4.0 was released.

@item 2005

@c mwolson@@gnu.org
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.

@item 2006

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

ERC became an official GNU project, and development moved to
@uref{https://sv.gnu.org/projects/erc}.  We switched to using GNU Arch as
our revision control system.  Our mailing list address changed as well.

@item 2007

We switched to using git for our version control system.

@item 2009+

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

@end itemize

@node GNU Free Documentation License
@appendix GNU Free Documentation License
@include doclicense.texi

@node Concept Index
@unnumbered Index

@printindex cp

@bye