Specifically, the reference is to so-called GNU messages in the clacks system, where GNU is a prefix code meaning “send the message on, do not log, and turn the

Specifically, the reference is to so-called GNU messages in the clacks system, where GNU is a prefix code meaning “send the message on, do not log, and turn the message around at the end of the line and send it back again”. These messages were used as memorials for deceased clacks workers - the message would never be delivered, and would stay in the system for as long as the clacks stay running. Hence, the worker’s name will be spoken for - hopefully -eternity.