diff --git a/Software/Development/Language/Go/Basic/Golang_安装_Packages.md b/Software/Development/Language/Go/Basic/Golang_安装_Packages.md
index 7b7bc53..fecebfe 100644
--- a/Software/Development/Language/Go/Basic/Golang_安装_Packages.md
+++ b/Software/Development/Language/Go/Basic/Golang_安装_Packages.md
@@ -11,12 +11,20 @@ go env -w GO111MODULE=on
 go env -w GOPROXY=https://goproxy.cn
 ```
 
-## 2.安装 Packages
+## 2.下载和安装 Packages
 
-以安装 guru 为例：
+通常，开发过程中所需要的 Package 只需要通过 go get 命令下载就可以使用，以 uuid 包为例，下载指定版本的 uuid 包命令如下：
 
 ```bash
-go get golang.org/x/tools/cmd/guru
-go build golang.org/x/tools/cmd/guru
-mv guru $(go env GOROOT)/bin
+# 下载 Go Package
+go get github.com/satori/go.uuid@v1.2.0
+```
+
+有些 go 工具除了下载外还需要编译安装，以 gopls 工具为例，下载、编译和安装命令如下：
+
+```bash
+# 下载 gopls
+go get -v golang.org/x/tools/gopls
+# 编译并安装
+go install golang.org/x/tools/gopls
 ```
diff --git a/Software/Development/Language/Go/Basic/Golang_文件操作.md b/Software/Development/Language/Go/Basic/Golang_文件操作.md
index 5879d87..fbc4bad 100644
--- a/Software/Development/Language/Go/Basic/Golang_文件操作.md
+++ b/Software/Development/Language/Go/Basic/Golang_文件操作.md
@@ -31,7 +31,7 @@ func Open(name string) (*File, error)
 func OpenFile(name string, flag int, perm FileMode) (*File, error)
 ```
 
-perm 模式如下：
+flag 如下：
 
 ```go
 //打开方式
@@ -55,6 +55,47 @@ O_TRUNC int = syscall.O_TRUNC // if possible, truncate file when opened.
 )
 ```
 
+perm 模式如下：
+
+```go
+const (
+    // The single letters are the abbreviations
+    // used by the String method's formatting.
+    // 文件夹模式
+    ModeDir        FileMode = 1 << (32 - 1 - iota) // d: is a directory
+    // 追加模式
+    ModeAppend                                     // a: append-only
+    // 单独使用
+    ModeExclusive                                  // l: exclusive use
+    // 临时文件
+    ModeTemporary                                  // T: temporary file; Plan 9 only
+    // 象征性的关联
+    ModeSymlink                                    // L: symbolic link
+    // 设备文件
+    ModeDevice                                     // D: device file
+    // 命名管道
+    ModeNamedPipe                                  // p: named pipe (FIFO)
+    // Unix 主机 socket
+    ModeSocket                                     // S: Unix domain socket
+    // 设置uid
+    ModeSetuid                                     // u: setuid
+    // 设置gid
+    ModeSetgid                                     // g: setgid
+    // UNIX 字符串设备，当设备模式是设置unix
+    ModeCharDevice                                 // c: Unix character device, when ModeDevice is set
+    // 粘性的
+    ModeSticky                                     // t: sticky
+    // 非常规文件；对该文件一无所知
+    ModeIrregular                                  // ?: non-regular file; nothing else is known about this file
+
+    // bit位遮盖，不变的文件设置为none
+    // Mask for the type bits. For regular files, none will be set.
+    ModeType = ModeDir | ModeSymlink | ModeNamedPipe | ModeSocket | ModeDevice | ModeCharDevice | ModeIrregular
+    // 权限位
+    ModePerm FileMode = 0777 // Unix permission bits
+)
+```
+
 ### 1.3.获取文件状态
 
 ```go