XDCC (Xabi DCC or eXtended DCC) was initially a script written in 1994 for ircII by Xabi. This script extends the ircII DCC command.

Now XDCC refers to IRC bots running file sharing programs in general. XDCC bots serve one or more typically large files for download using the DCC protocol. Though XDCC is frequently employed in distributing illegal content, such as warez releases of software, music, and movies, it can also be used in legal ways.

XDCC is quickly gaining popularity over older mediums of software piracy such as newsgroups and fserve. Unlike peer-to-peer transfers, XDCC servers are often hosted on connections with very high upstream bandwidth, sometimes in excess of 100 Mbit. Often FTP servers are also running on the XDCC servers to facilitate uploading of materials to them. Some XDCC servers run on hacked computers.

To use XDCC, one can send a private message (query) or send a CTCP command to a bot, using an IRC client. The user can ask a bot what files it has by private messaging "xdcc list" to the bot. However, this feature is often disabled as to not attract too much attention. When a user wants to download a packet or file from a bot, the user would type something such as "xdcc send #" to the bot. The bot will either start sending the user the packet or the bot will place the user in a queue, and force the user to wait their turn.

Common (Iroffer) XDCC Commands

Unless otherwise noted, most commands may be sent via ctcp instead of msg. Some servers disable msg commands.

/msg xdcc send # - Requests the specified pack number from the bot.

/msg xdcc list - Requests a list of packs available from the bot.

/msg xdcc remove - Removes all files one has queued for sending. (This only works via msg.)

/msg xdcc remove # - Removes the file in the specified queue position. (This only works via msg.)

/msg xdcc info # - Requests information about the specified pack number.