Butler stream servers can generate client address.

logdog/client/butlerlib/streamclient/client_namedPipe_windows.go

 // Copyright 2015 The LUCI Authors. All rights reserved.
 // Use of this source code is governed under the Apache License, Version 2.0
 // that can be found in the LICENSE file.
 
 package streamclient
 
 import (
         "errors"
-        "fmt"
         "io"
 
         npipe "gopkg.in/natefinch/npipe.v2"
 )
 
 // Register POSIX-only protocols.
 func init() {
         registerProtocol("net.pipe", newNamedPipeClient)
 }
 
 // newNamedPipeClient creates a new Client instance bound to a named pipe stream
 // server.
 func newNamedPipeClient(path string) (Client, error) {
         if path == "" {
                 return nil, errors.New("streamclient: cannot have empty named pipe path")
         }
 
         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
+}