Hack 76 Set Up an Eggdrop Bot

Eggdrops have been around for quite a few years, so plenty of authors have had time to write Tcl scripts or C modules that make these kinds of bots very powerful. This hack shows you how to install and set up a simple Eggdrop.

Eggdrop is the oldest IRC bot still in active development. It supports multiple channels and can be extended using Tcl scripts or C modules—thousands of which can be downloaded freely to perform common tasks, which Eggdrop does not support natively.

Downloading, installing, and configuring Eggdrop is relatively simple. The first step is to connect to the server you will run the bot on, probably via SSH or Telnet. When you are connected, you can obtain a copy of the Eggdrop source code. The easiest way to obtain the latest version of the source code is to use wget. If you type wget eggheads.org, the current (stable) version of the Eggdrop code will be downloaded to the current directory, as shown in Figure 12-1.

Figure 12-1. Using wget to get the Eggdrop source code

If your server does not have wget installed or you would rather not use it, you can download the files manually from http://www.eggheads.org and upload the files to the server via FTP or SCP.

The Eggdrop source code is distributed as a tarball, so the next thing to do is "untar" it. This is done using the tar command, like so:

% tar zxvf eggdrop1.6.15.tar.gz

You may need to change the filename if you have downloaded a more recent version.

This will copy all of the files in the tarball to a new directory, as shown in Figure 12-2.

Figure 12-2. Eggdrop extracted into its own directory

Now change to the new directory:

% cd eggdrop1.6.15

If you are curious about Eggdrop, you may want to read the README and INSTALL files. They contain information on installing and running Eggdrop. When you have read these files, you can run Eggdrop's configure script:

% ./configure

This allows Eggdrop to adjust its settings so it can work correctly on your system. When this has finished, type:

% make config

This allows Eggdrop to configure the modules it needs. When the default modules have finished compiling, you should see something like Figure 12-3.

Figure 12-3. Configuring the required modules with make config

Next, you can type:

% make

This will compile the bot, but it may take a few minutes depending on the speed of your server. Now you're ready to install the bot. Type this:

% make install

and you should see something like Figure 12-4.

Figure 12-4. Installing Eggdrop

This will install Eggdrop into ~/eggdrop—that is, it will create an eggdrop directory in your home directory. cd to this folder, and you are now ready to edit the configuration file for your Eggdrop.

12.5.1 Configuring Eggdrop

The first step is to open the config file in your favorite editor, for example:

% pico -w eggdrop.conf

As you look through the file, remember that all the lines that begin with a hash (#) are comments and will not be interpreted by Eggdrop. You can safely ignore most of these if you're in a rush, but they can often provide valuable help when it comes to setting up the more exotic features.

Most of Eggdrop's settings are in the form of set variable "value", which assigns the "value" to the variable. For example set nick "Hacky" would set the Eggdrop's nickname to "Hacky." The most important settings follow:

username

This is the login that Eggdrop will use as its Ident if there is no identd running.

admin

This should tell users how to contact the administrator of the bot (most likely you). The information is given out when a user types /msg bot help.

network

This is used only if you are linking your Eggdrop to another bot and allows the bots to establish a connection whether they are on the same network or not. It should be either the name of the network (for example, "freenode") or a server name.

timezone

This controls which time zone the bot will be running in and should probably be set to the same time zone as the server.

userfile

This determines where Eggdrop will look for its user file. This contains details about all of the users known to the bot. It can be named anything you like. Something like hacky.users is the easiest to keep track of, however.

listen

This command takes a different format than most others. The syntax is listen port type, and it needs to be uncommented and altered if you wish to link your Eggdrop to other bots or if you wish to telnet to it. Chose a number for the port, somewhere between 1024 and 10000, and make sure the # is removed from the line.

owner

This command is required for your bot to recognize you as its owner. Uncomment the line, and replace the value with the nickname you use on IRC.

die

A few lines beneath the owner setting is a line beginning with die. This must be removed or commented out; otherwise your bot will not start. This is cunningly placed there to ensure that people edit the config file fully before using the bot.

chanfile

This is the file that Eggdrop will store its channels and settings in. You may like to name it in a similar fashion to the user file.

net-type

This setting allows the bot to determine which commands it can use on the server it is connecting to. Most networks will probably be of type "other."

nick

This is the nickname the bot uses on IRC. It can be anything you like, as long as the IRC server allows it. Most servers will not allow a nickname beginning with numbers, for example.

altnick

This is the nickname the bot will try to use if its preferred nickname is in use. It can contain a question mark, which tells Eggdrop to insert a random number at that point. For example, setting this to "Hacky?" could result in the nick ending up as "Hacky123."

realname

This is what will be displayed as the bot's real name on IRC. Most people set this to "/msg botname hello" or list the bot's primary channel. Other users are then able to view this information when they type /whois hacky.

servers

This is a list of servers the bot will try to connect to. Delete the two examples and add the addresses of one or more servers on the network you want the bot to connect to.

learn-users

This controls whether users can create their own account on the bot by saying "hello" to it. Setting it to "1" will make it easier to set up the bot via IRC.

notefile

This is the file in which the bot will store notes (messages from one user to another). This should probably be named similarly to the user file.

die

Shortly after the notefile setting is another die command that needs to be commented out.

blowfish

This is a commented-out loadmodule command. You must uncomment this line, as blowfish is required to encrypt the passwords in the bot's user file.

When you have finished editing the file, save the changes and quit back to the shell. You can now start the bot by typing:

% ./eggdrop -m eggdrop.conf

This launches the bot for the first time. To run it again, type:

% ./eggdrop eggdrop.conf

—Chris Smith