Function wrote 

pub fn wrote(p: &Path, before: Option<&str>, change: Change, talk: bool)

Records a write of the log at p under its lock (every writer: send, ack, borg-mesh sync.rs store_messages): before, the log’s mark before it (mark_of; None: no log); change, what it did to the log; talk, whether it wrote a tell, ask or steer. The generation stays only for Seen lines appended to the log as the record left it, or added by a rewrite that removed only lines past the TTL (Change::Expired), with nothing else written meanwhile (the length says so); anything else moves it, to at least now in ns, so a record made anew never repeats one a reader holds. Best effort: a record that is not the log’s makes talk fall back to the log’s mark.