Warn for readonly instead of setting option

Fixes #2106

cmd/micro/micro.go

@@ -319,6 +319,8 @@ func main() {
 		screen.TermMessage(err)
 	}
 
+	action.InitGlobals()
+	buffer.SetMessager(action.InfoBar)
 	args := flag.Args()
 	b := LoadInput(args)
 
@@ -329,7 +331,6 @@ func main() {
 	}
 
 	action.InitTabs(b)
-	action.InitGlobals()
 
 	err = config.RunPluginFn("init")
 	if err != nil {

internal/buffer/buffer.go

@@ -252,8 +252,9 @@ func NewBufferFromFileAtLoc(path string, btype BufType, cursorLoc Loc) (*Buffer,
 		buf = NewBuffer(file, util.FSize(file), filename, cursorLoc, btype)
 	}
 
-	if readonly {
-		buf.SetOptionNative("readonly", true)
+	if readonly && prompt != nil {
+		prompt.Message("Warning: file is readonly - sudo will be attempted when saving")
+		// buf.SetOptionNative("readonly", true)
 	}
 
 	return buf, nil

internal/buffer/message.go

@@ -82,3 +82,13 @@ func (b *Buffer) ClearMessages(owner string) {
 func (b *Buffer) ClearAllMessages() {
 	b.Messages = make([]*Message, 0)
 }
+
+type Messager interface {
+	Message(msg ...interface{})
+}
+
+var prompt Messager
+
+func SetMessager(m Messager) {
+	prompt = m
+}