Butler stream servers can generate client address.

logdog/client/butlerlib/streamclient/client_namedPipe_windows.go

Index: logdog/client/butlerlib/streamclient/client_namedPipe_windows.go
diff --git a/logdog/client/butlerlib/streamclient/client_namedPipe_windows.go b/logdog/client/butlerlib/streamclient/client_namedPipe_windows.go
index 5198dbd93b4c46279c880ed6dacd38c1b874c1b9..c04fcd7464283b0bc38e445fd6b8f5deafe39e62 100644
--- a/logdog/client/butlerlib/streamclient/client_namedPipe_windows.go
+++ b/logdog/client/butlerlib/streamclient/client_namedPipe_windows.go
@@ -6,7 +6,6 @@ package streamclient
 
 import (
 	"errors"
-	"fmt"
 	"io"
 
 	npipe "gopkg.in/natefinch/npipe.v2"
@@ -26,7 +25,12 @@ func newNamedPipeClient(path string) (Client, error) {
 
 	return &clientImpl{
 		factory: func() (io.WriteCloser, error) {
-			return npipe.Dial(fmt.Sprintf(`\\.\pipe\%s`, path))
+			return npipe.Dial(LocalNamedPipePath(path))
 		},
 	}, nil
 }
+
+// LocalNamedPipePath returns the path to a local Windows named pipe named base.
+func LocalNamedPipePath(base string) string {
+	return `\\.\pipe\` + base
+}