From time to time Changi will receive so called control
messages, which instruct the server to
Cancel an article
Create a new newsgroup or update the mode of an existing one
Remove outdated newsgroups
Cancelled articles will be removed by Changi immediately.
With the other types of control messages, Changi will
perform the action specified in
control.ctl or, if that file
doesn't exist, create or update two command files,
newgroup.cmd for newgroup control messages and
rmgroup.cmd for rmgroup control messages, containing related
calls to Chanco to create,
remove or update the active file. You may inspect these
files with an editor before running them.