Constant EV_LEN 

pub const EV_LEN: usize = _; // 34usize

Wire length of one event: seq(4) + at_s(4, STAMPED BY THE SINK) + caller[12] + peer[12] + op(1) + kind(1).

The peer is carried as a NAME, not an endpoint or a cap slot, and that is the whole point. A cap slot is local to the emitter and means nothing to a reader; an endpoint id needs a second lookup. The emitter called request_with_reply("fs", ...) - it KNOWS the name, and a name is what a reader wants. This is the “symbolic” half the requirement asked for, and it is only reachable out here: the kernel may not interpret a protocol, but the service that owns one may (§4.4, §26.10).