Butler stream servers can generate client address.

logdog/client/butler/streamserver/namedPipe_windows.go

Index: logdog/client/butler/streamserver/namedPipe_windows.go
diff --git a/logdog/client/butler/streamserver/namedPipe_windows.go b/logdog/client/butler/streamserver/namedPipe_windows.go
index e848d56cdb0ddc087513b483eaad61cce32d3c67..d1245541fe9b8a16c5f6d506780eb121c6b96dba 100644
--- a/logdog/client/butler/streamserver/namedPipe_windows.go
+++ b/logdog/client/butler/streamserver/namedPipe_windows.go
@@ -7,19 +7,40 @@ package streamserver
 import (
 	"net"
 
+	"github.com/luci/luci-go/common/errors"
 	log "github.com/luci/luci-go/common/logging"
+
 	"golang.org/x/net/context"
 	npipe "gopkg.in/natefinch/npipe.v2"
 )
 
+// localNamedPipePrefix is the prefix that can be applied to a named pipe in
+// order to bind it exclusively to the local system.
+const localNamedPipePrefix = `\\.\pipe\`
+
+// maxWindowsNamedPipeLength is the maximum length of a Windows named pipe.
+const maxWindowsNamedPipeLength = 256
+
 // NewNamedPipeServer instantiates a new Windows named pipe server instance.
-func NewNamedPipeServer(ctx context.Context, address string) StreamServer {
-	ctx = log.SetField(ctx, "address", address)
+func NewNamedPipeServer(ctx context.Context, name string) (StreamServer, error) {
+	switch l := len(name); {
+	case l == 0:
+		return nil, errors.New("cannot have empty name")
+	case l > maxWindowsNamedPipeLength:
+		return nil, errors.Reason("name exceeds maximum length %(max)d").
+			D("name", name).
+			D("max", maxWindowsNamedPipeLength).
+			Err()
+	}
+
+	name = localNamedPipePrefix + name

[nodir, 2017/03/06 22:29:44]

this may be more than maxWindowsNamedPipeLength?

[dnj, 2017/03/06 22:39:30]

This is fine - the name length is about the pipe name, not the full pipe path.

+	ctx = log.SetField(ctx, "name", name)
 	return &listenerStreamServer{
 		Context: ctx,
+		address: "net.pipe:" + name,
 		gen: func() (net.Listener, error) {
 			log.Debugf(ctx, "Creating Windows server socket Listener.")
-			return npipe.Listen(address)
+			return npipe.Listen(name)
 		},
-	}
+	}, nil
 }