Bound the messages held for a shutdown, and report a partial receipt

README.md

@@ -101,7 +101,7 @@ Every one is optional.
 | `enquireLinkInterval` | `20000` | How often to send `enquire_link` on a quiet link. |
 | `idleTimeout` | `2 × enquireLinkInterval` | Give up on a link the peer has stopped answering, and re-bind unless `reconnect` is `false`. |
 | `responseTimeout` | `30000` | How long to wait for a response before giving up on it, and how long a send with no link waits for the next one; `0` waits forever. |
-| `shutdownTimeout` | `5000` | How long `close()` and `unbind()` wait for the requests this end already sent and the messages the application has not answered. `0` waits forever for the requests, which the peer answers or times out; the messages fall back to `responseTimeout`, or to its default where that is 0 too, since nothing but the application ends that wait. |
+| `shutdownTimeout` | `5000` | How long `close()` and `unbind()` wait for the requests this end already sent and the messages the application has not answered. `0` waits forever for the requests, which end when the peer answers or `responseTimeout` expires — so setting both to `0` never ends. The messages fall back to `responseTimeout`, or to its default where that is `0` too, since nothing but the application ends that wait. |
 | `maxOutstanding` | `10` | Requests allowed on the wire at once; further sends queue. |
 | `smsIdFormat` | — | The notation the SMSC writes message ids in, per place it writes them: `{ receipt: 'decimal', submitResp: 'hex' }`. Only needed where the two disagree. |
 | `reconnect` | on | Re-binds after a drop, an idle timeout, or a stream the library cannot read, backing off from `minDelay` 1 s to `maxDelay` 30 s and starting over at `minDelay` once a link has lasted `maxDelay`. `{ minDelay, maxDelay }` retunes it; `false` turns it off, so a drop ends the session. |