pub fn selective_receive() -> ChunkExpand description
Selective Atomic Hop: server waits for TAG_REQ while a TAG_JUNK hop
sits ahead in the mailbox (FIFO skip, not drop).
Requires crate::std_native_table.
mainsends junk (tag=TAG_JUNK), then request (tag=TAG_REQ, payload=41)serverdoesReceiveMatchImm TAG_REQ— must see payload 41, not junk- replies
TAG_REP/ 42; then classicReceivedrains the leftover junk mainreturns reply payload42