const wantString = testPayload + testPayload
		if resp.OrgString != testPayload+testPayload {
			t.Errorf("want %q, got %q", wantString, resp.OrgString)
		}
		if resp.OrgNum != n+1 {
			t.Errorf("want %d, got %d", n+1, resp.OrgNum)
		}
		handler.PutResponse(resp)
		n++
		return nil
	})
	errFatal(err)
	t.Log("EOF.", payloads, " Roundtrips:", time.Since(start))
}

			defer PutByteBuffer(payload)
			return append(GetByteBuffer()[:0], payload...), nil
		}))
		errFatal(rpc.Register(remote, func(req *testRequest) (resp *testResponse, err *RemoteErr) {
			return &testResponse{
				OrgNum:    req.Num,
				OrgString: req.String,
				Embedded:  *req,
			}, nil
		}))
		errFatal(err)
	}
	const payloadSize = 512
	rng := rand.New(rand.NewSource(time.Now().UnixNano()))

// The opening parenthesis has been absorbed.
func (in *Input) argsFor(macro *Macro) map[string][]Token {
	var args [][]Token
	// One macro argument per iteration. Collect them all and check counts afterwards.
	for argNum := 0; ; argNum++ {
		tokens, tok := in.collectArgument(macro)
		args = append(args, tokens)
		if tok == ')' {
			break
		}
	}
	// Zero-argument macros are tricky.