下载安装git客户端 http://code.google.com/p/git-osx-installer/downloads/list?can=3

       注册github账号 https://github.com/ -->Pricing and Signup -->Create a free account

创建ssh：

       在local打开terminal：

       $cd ～/.ssh  检查是否已经存在ssh

       如果存在，先将已有的ssh备份，或者将新建的ssh生成到另外的目录下

       如果不存在，通过默认的参数直接生成ssh

       生成过程如下：

       $ssh-keygen -t rsa -C xxxxx@gmail.com（注册github时的email）

        Generating public/private rsa key pair.

        Enter file in which to save the key (/Users/twer/.ssh/id_rsa):   //一般都是默认直接回车

        Created directory '/Users/twer/.ssh'.

        Enter passphrase (empty for no passphrase):    //这个密码是push的时候需要输入的

        Enter same passphrase again: 

        Your identification has been saved in /Users/twer/.ssh/id_rsa.

        Your public key has been saved in /Users/twer/.ssh/id_rsa.pub.

        The key fingerprint is:

        18:16:11:c9:01:6c:48:09:7f:27:c6:43:0d:7f:3f:84 xxxxx@gmail.com

        The key's randomart image is:

        +--[ RSA 2048]----+

        |.o.++===         |

        |.ooo.+. .       |

        |  ..* = E .      |

        |   o = + o       |

        |      . S o      |

        |           .     |

        |                 |

        |                 |

        |                 |

       +-----------------+

       如果要修改ssh生成目录，在蓝色位置处输入要生成的路径，选择默认的话，会生成在 ～/.ssh下

在github中添加ssh：

       登陆github，选择Account Settings-->SSH Public Keys 添加ssh

       Title：xxxxx@gmail.com

       Key：打开你生成的id_rsa.pub文件，将其中vi其内容拷贝至此 

测试SSH：

       $ssh git@github.com

        The authenticity of host 'github.com (207.97.227.239)' can't be established.

        RSA key fingerprint is 16:27:ac:a5:76:28:2d:36:63:1b:56:4d:eb:df:a6:48.

        Are you sure you want to continue connecting (yes/no)? yes

        Warning: Permanently added 'github.com,207.97.227.239' (RSA) to the list of known hosts.

        PTY allocation request failed on channel 0

        Hi xianfuying! You've successfully authenticated, but GitHub does not provide shell access.

                Connection to github.com closed.

        在蓝色位置处输入 yes

设置本地git个人信息：

        $git config --global user.name "your real name"

        $git config --global user.email "xxxxx@gmail.com"

至此，git和github的设置就完成了，下面就是如何将本地代码push到github上，以及如何从github上pull代码了：

在github中创建Repository：

      https://github.com/ --> New Repository 输入Repository信息 projectName

在本地创建代码库：

      创建一个文件夹作为local repository

      $mkdir test

      创建一个文件

       $cd test

       $vi test.txt

       将文件添加至local repository

       $git add test.txt

       初始化local repository

       $git init

       commit文件

       $git commit -a

       定义远程服务器别名

       $git remote add alias git@github.com:xxxxx/projectName.git

       将本地数据push到github上

       $git push alias master

这样就可以将本地的代码push到github的repository中了

从github中pull代码：

      在github中搜到你想要pull的代码，如https://github.com/edgecase/ruby_koans

      选择fork，将此repository fock到你的repository下

      在本地创建local repository并初始化

      使用命令：

      $git pull git@github.com:xxxxx/ruby_koans.git

      将github上的代码pull到local repository中

当要push代码到git时，出现提示：

error:failed to push some refs to ...

Dealing with “non-fast-forward” errors
From time to time you may encounter this error while pushing:

To prevent you from losing history, non-fast-forward updates were rejected
Merge the remote changes before pushing again.  See the 'non-fast forward'
section of 'git push --help' for details.
This error can be a bit overwhelming at first, do not fear. Simply put, git cannot make the change on the remote without losing commits, so it refuses the push. Usually this is caused by another user pushing to the same branch. You can remedy this by fetching and merging the remote branch, or using pull to perform both at once.
In other cases this error is a result of destructive changes made locally by using commands like git commit --amend or git rebase. While you can override the remote by adding --force to the push command, you should only do so if you are absolutely certain this is what you want to do. Force-pushes can cause issues for other users that have fetched the remote branch, and is considered bad practice. When in doubt, don’t force-push.

 

http://my.csdn.net/uploads/201204/19/1334803176_7047.png- 下git与github简单使用 (出错处理)" />

问题（Non-fast-forward）的出现原因在于：git仓库中已经有一部分代码，所以它不允许你直接把你的代码覆盖上去。于是你有2个选择方式：

1，强推，即利用强覆盖方式用你本地的代码替代git仓库内的内容

git push -f

2，先把git的东西fetch到你本地然后merge后再push

$ git fetch

$ git merge

这2句命令等价于

可是，这时候又出现了如下的问题：

http://my.csdn.net/uploads/201204/19/1334803661_1873.png- 下git与github简单使用 (出错处理)" />

上面出现的 [branch "master"]是需要明确(.git/config)如下的内容
[branch "master"]
    remote = origin

    merge = refs/heads/master

这等于告诉git2件事:

1，当你处于master branch, 默认的remote就是origin。

2，当你在master branch上使用git pull时，没有指定remote和branch，那么git就会采用默认的remote（也就是origin）来merge在master branch上所有的改变

如果不想或者不会编辑config文件的话，可以在bush上输入如下命令行：

之后再重新git pull下。最后git push你的代码吧。it works now~

DIY Demo（以后用就这么几步）

mac:github $ git init
Initialized empty Git repository in /Users/loveuu/github/.git/
mac:github $ git add Snapshots/
mac:github $ git commit -a

mac:github $ git remote add alias git@github.com:braveryhui/MyXcodeSnapShot.git
mac:github $ git push alias master

假如那个repository是新建的里面没有内容就需要这么来push是第一次

 

touch README.md
git init
git add README.md
git commit -m "first commit"
git remote add origin git@github.com:braveryhui/UItextViewMoveUp.git
git push -u origin master

假如git push的时候出现提示密码 那么就就需要重新执行这个的时候不输入密码

参考

http://apps.hi.baidu.com/share/detail/16068052

http://blog.csdn.net/banxi1988/article/details/6555293

http://apps.hi.baidu.com/share/detail/31697631

安装引用http://blog.163.com/xianfuying@126/blog/static/21960005201181482518631/