Committed. I noticed that there are several characters with no match in protocol.h. It might be worth adding those.
In walsender.c: 1537: pq_sendbyte(ctx->out, 'w'); 2353: case 'r': 2357: case 'h': 2361: case 'p': 2755: pq_sendbyte(&output_message, 's'); 3367: pq_sendbyte(&output_message, 'w'); 4138: pq_sendbyte(&output_message, 'k'); In walreceiver.c: 829: case 'w': /* WAL records */ 853: case 'k': /* Keepalive */ 1133: pq_sendbyte(&reply_message, 'r'); 1237: pq_sendbyte(&reply_message, 'h'); In logical/worker.c: 3854: if (c == 'w') 3876: else if (c == 'k') 3895: else if (c == 's') /* Primary status update */ 4127: pq_sendbyte(reply_message, 'r'); 4298: pq_sendbyte(request_message, 'p'); -- nathan