Informs the owners and hosts of a channel that a user has tried to enter the channel and could not (could be because of a full channel, keyword wrong, user ban, or other reasons). This message is only sent to the IRCX owners and hosts of the channel.
Syntax:
:<user> KNOCK <channel> <reason>
<user> User field is of the format nick!userid@host.
<channel> Name of the channel that the user tried to enter.
<reason> Reason that the user received when they tried to join the channel.