Linux学习篇（六）：学习 git

逛 github 时面对git 、make 无从下手？本文先来介绍 git 。

git 用于文本文件的版本管理，git 作者与 Linux 内核作者是同一个人——林纳斯。

初次学习 git 搭配 BeyondCompare 会更香哦。

安装git：

1	`<<huaecase@Huaecase ~ >>$` `sudo` `apt` `install` `git`

建立工作区( 建议在一个空文件夹内)：

<<huaecase@Huaecase ~/gitwork >>$  mkdir gitwork
<<huaecase@Huaecase ~/gitwork >>$  cd gitwork
<<huaecase@Huaecase ~/gitwork >>$  git init

　　产生了隐藏文件：

1	`<<huaecase@Huaecase ~/gitwork` `>>$` `ls` `-a .git`

新建文本文件 huae：

1	`<<huaecase@Huaecase ~/gitwork` `>>$ vim huae`

　　添加内容到huae:

1	`echo` `"first"` `> huae`　　　　　　 `# '>' 和 '>>' 代表输出重定向 '>' 为替换模式而 '>>' 为追加。`

将huae提交到git 缓存区：

1	`<<huaecase@Huaecase ~/gitwork` `>>$ git add huae`

将huae提交到 git 本地仓库：

<<huaecase@Huaecase ~/gitwork >>$  git commit huae -m "first commit"
 
*** Please tell me who you are.
 
Run
 
  git config --global user.email "you@example.com"
  git config --global user.name "Your Name"
 
to set your account's default identity.
Omit --global to set the identity only in this repository.
 
fatal: empty ident name (for <huaecase@Huaecase.localdomain>) not allowed

　　首次使用要设置绑定的邮箱及账户名，解决后再次 commit。

<<huaecase@Huaecase ~/gitwork >>$  git config --global user.email "Huae@mail.com"
<<huaecase@Huaecase ~/gitwork >>$  git config --global user.name "Huae"
<<huaecase@Huaecase ~/gitwork >>$  git commit huae -m "first commit"
[master (root-commit) 6f44e7b] first commit
 1 file changed, 1 insertion(+)
 create mode 100644 huae

git status 查看状态：

<<huaecase@Huaecase ~/gitwork >>$  git status
On branch master
nothing to commit, working tree clean

git log 查看日志：

<<huaecase@Huaecase ~/gitwork >>$  git log
commit 6f44e7bb3e1f590d3c9ce5ea389becb41a29ec66 (HEAD -> master)
Author: Huae <Huaecase@gmail.com>
Date:   Mon Oct 5 17:35:24 2020 +0800
 
    first commit

　　git log 是站在当前版本节点看日志，版本切换后git log 内容也会跟着更改。而 git reflog 则是站在上帝视角看日志。

将huae 中的内容更改为 second并提交:

<<huaecase@Huaecase ~/gitwork >>$  echo "second" > huae
<<huaecase@Huaecase ~/gitwork >>$  git add huae
<<huaecase@Huaecase ~/gitwork >>$  git commit huae -m "second commit"

　　此时git log 和 git reflog：

<<huaecase@Huaecase ~/gitwork >>$    git log
commit cd64c55d4fedeffdea73379bd36b9c472430d2b7 (HEAD -> master)
Author: Huae <Huaecase@gmail.com>
Date: Mon Oct 5 17:45:21 2020 +0800
 
second commit
 
commit 6f44e7bb3e1f590d3c9ce5ea389becb41a29ec66
Author: Huae <Huaecase@gmail.com>
Date: Mon Oct 5 17:35:24 2020 +0800
 
first commit
<<huaecase@Huaecase ~/gitwork >>$    git reflog
cd64c55 (HEAD -> master) HEAD@{0}: commit: second commit
6f44e7b HEAD@{1}: commit (initial): first commit

回退到上一版本：

1	`<<huaecase@Huaecase ~/gitwork` `>>$ git reset --hard 6f44` `#6f44 是第一次提交后HEAD指向的 hard 的前一部分`

　　或者

1	`<<huaecase@Huaecase ~/gitwork` `>>$ git reset --hard HEAD^` `# HEAD 相当于指针， ^ 表示前一版本`

　　此时的 git log 和 git reflog:

<<huaecase@Huaecase ~/gitwork >>$  git log
commit 6f44e7bb3e1f590d3c9ce5ea389becb41a29ec66 (HEAD -> master)
Author: Huae <Huaecase@gmail.com>
Date:   Mon Oct 5 17:35:24 2020 +0800
 
    first commit
<<huaecase@Huaecase ~/gitwork >>$  git reflog
6f44e7b (HEAD -> master) HEAD@{0}: reset: moving to 6f44
cd64c55 HEAD@{1}: commit: second commit
6f44e7b (HEAD -> master) HEAD@{2}: commit (initial): first commit
<<huaecase@Huaecase ~/gitwork >>$