Run with internal flag when saving with sudo on Windows

cmd/micro/micro.go

@@ -38,6 +38,7 @@ var (
 	flagProfile   = flag.Bool("profile", false, "Enable CPU profiling (writes profile info to ./micro.prof)")
 	flagPlugin    = flag.String("plugin", "", "Plugin command")
 	flagClean     = flag.Bool("clean", false, "Clean configuration directory")
+	flagWrite     = flag.String("write", "", "Write file (internal)")
 	optionFlags   map[string]*string
 
 	sighup chan os.Signal
@@ -223,6 +224,25 @@ func LoadInput(args []string) []*buffer.Buffer {
 	return buffers
 }
 
+func write(name string) (err error) {
+	var f *os.File
+
+	if f, err = os.OpenFile(*flagWrite, os.O_WRONLY|os.O_CREATE, 0666); err != nil {
+		return
+	}
+	if err = f.Truncate(0); err != nil {
+		return
+	}
+	if _, err = io.Copy(f, os.Stdin); err != nil {
+		return
+	}
+	if err = f.Close(); err != nil {
+		return
+	}
+
+	return
+}
+
 func main() {
 	defer func() {
 		if util.Stdout.Len() > 0 {
@@ -246,6 +266,14 @@ func main() {
 		defer pprof.StopCPUProfile()
 	}
 
+	if *flagWrite != "" {
+		if err := write(*flagWrite); err != nil {
+			fmt.Println(err)
+			os.Exit(1)
+		}
+		return
+	}
+
 	InitLog()
 
 	err = config.InitConfigDir(*flagConfigDir)

internal/buffer/save.go

@@ -34,7 +34,17 @@ func overwriteFile(name string, enc encoding.Encoding, fn func(io.Writer) error,
 	var c chan os.Signal
 
 	if withSudo {
-		cmd = exec.Command(config.GlobalSettings["sucmd"].(string), "dd", "bs=4k", "of="+name)
+		sucmd := config.GlobalSettings["sucmd"].(string)
+		if runtime.GOOS == "windows" {
+			exe, err := os.Executable()
+			if err == nil {
+				cmd = exec.Command(sucmd, exe, "-write", name)
+			} else {
+				return err
+			}
+		} else {
+			cmd = exec.Command(sucmd, "dd", "bs=4k", "of="+name)
+		}
 
 		if writeCloser, err = cmd.StdinPipe(); err != nil {
 			return
@@ -130,9 +140,6 @@ func (b *Buffer) saveToFile(filename string, withSudo bool, autoSave bool) error
 	if b.Type.Scratch {
 		return errors.New("Cannot save scratch buffer")
 	}
-	if withSudo && runtime.GOOS == "windows" {
-		return errors.New("Save with sudo not supported on Windows")
-	}
 
 	if !autoSave && b.Settings["rmtrailingws"].(bool) {
 		for i, l := range b.lines {