add some useful logs

Author: umbynos

main.go

@@ -135,6 +135,7 @@ func main() {
 		newPath := updater.BinPath(path)
 		err := copyExe(path, newPath)
 		if err != nil {
+			log.Println("Copy error: ", err)
 			panic(err)
 		}
 
@@ -153,10 +154,12 @@ func main() {
 func copyExe(from, to string) error {
 	data, err := ioutil.ReadFile(from)
 	if err != nil {
+		log.Println("Cannot read file: ", from)
 		return err
 	}
 	err = ioutil.WriteFile(to, data, 0755)
 	if err != nil {
+		log.Println("Cannot write file: ", to)
 		return err
 	}
 	return nil