<1>git 遇到的困难

一、使用git在本地创建一个项目的过程
首先得在github或者git@OSC上创建一个hello-world项目。本地才能进行推送
$ makdir ~/hello-world //创建一个项目hello-world
$ cd ~/hello-world //打开这个项目
$ git init //初始化
$ touch README
$ git add README //更新README文件
$ git commit -m ‘first commit’ //提交更新，并注释信息“first commit”
$ git remote add origin git@github.com:defnngj/hello-world.git //连接远程github项目当然 origin还可以 origin_new
$ git push -u origin master //将本地项目更新到github项目上去

执行：git push -u origin master -f 以及 git push origin master

二、其他常用命令：
git remote -v //查看地址
git config —list //查看配置
git status //查看状态
git remote rm origin //删除origin这个push地址
rm -rf ~/.ssh 删除.ssh 文件和文件夹
rm -f ~/.ssh 删除文件

三、git push遇到的问题：
本来想用 ssh传输的，结果用ssh传输总是报错：

Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git remote add origin git@git.oschina.net:MaGary/SpringMVC.git
Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git push -u origin master
Access denied.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights
and the repository exists.
Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git pull
Access denied.
fatal: Could not read from remote repository.
Please make sure you have the correct access rights

先在gitHUb或则Git@OSC上创建项目。后来我改用 https地址提交项目：
https://git.oschina.net/MaGary/SpringMVC.git/

重新设置remote地址： git remote add origin https://git.oschina.net/MaGary/SpringMVC.git

接着进行 push操作：结果报错：（git push -u origin master 以及 git push origin master）度有错：都是：![rejected] master -> master(fetch first); ![rejected] master -> master(non-fast-forward);

Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git push -u origin master
Username for 'https://git.oschina.net': fshengbing0327@163.com
To https://git.oschina.net/MaGary/SpringMVC.git
 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'https://git.oschina.net/MaGary/SpringMVC.git'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.
Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git push origin master
Username for 'https://git.oschina.net': fshengbing0327@163.com
To https://git.oschina.net/MaGary/SpringMVC.git
 ! [rejected]        master -> master (non-fast-forward)
error: failed to push some refs to 'https://git.oschina.net/MaGary/SpringMVC.git'
hint: Updates were rejected because the tip of your current branch is behind
hint: its remote counterpart. Integrate the remote changes (e.g.
hint: 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

解决办法：

执行：git push -u origin master -f 以及 git push origin master

Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git push -u origin master -f
Username for 'https://git.oschina.net': fshengbing0327@163.com
Counting objects: 253, done.
Delta compression using up to 4 threads.
Compressing objects: 100% (204/204), done.
Writing objects: 100% (253/253), 7.63 MiB | 1.43 MiB/s, done.
Total 253 (delta 74), reused 0 (delta 0)
remote: Resolving deltas: 100% (74/74), done.
To https://git.oschina.net/MaGary/SpringMVC.git
 + 8cdf4d4...d7e93f6 master -> master (forced update)
Branch master set up to track remote branch master from origin.
Administrator@PC201611290918 MINGW64 /d/Git@OSC/SpringMVC (master)
$ git push origin master
Username for 'https://git.oschina.net': fshengbing0327@163.com
Everything up-to-date

<2>git push 的错误failed to push some refs to

当我们在github版本库中发现一个问题后，你在github上对它进行了在线的修改；或者你直接在github上的某个库中添加readme文件或者其他什么文件，但是没有对本地库进行同步。这个时候当你再次有commit想要从本地库提交到远程的github库中时就会出现push失败的问题。

如下图所示
我在github库中对某个文件进行了在线的编辑，并且没有同步到本地库，之后我在本地库添加了文件test.txt，并想提交到github，出现以下错误：error：failed to push some refs to。
gitpush失败

解决方案

这个问题是因为远程库与本地库不一致造成的，那么我们把远程库同步到本地库就可以了。
使用指令

git pull --rebase origin master

这条指令的意思是把远程库中的更新合并到本地库中，–rebase的作用是取消掉本地库中刚刚的commit，并把他们接到更新后的版本库之中。

如图：
gitpush

下面我用图形象的解释下错误情况的发生和解决

gitpush失败2
git pull –rebase origin master意为先取消commit记录，并且把它们临时保存为补丁(patch)(这些补丁放到”.git/rebase”目录中)，之后同步远程库到本地，最后合并补丁到本地库之中。
gitpush失败3
接下来就可以把本地库push到远程库当中了。
gitpush失败4