ubuntu命令行使用github

1、问题：执行git remote add origin git@github.com:yylxm/Git.git

                    出现问题fatal: remote origin already exists.

        解决办法：git remote显示所有的远程库，然后采用git remote rm origin删除该origin。

2、问题： 采用git push -u origin master推送本地库到github
                   出现问题fatal: I don't handle protocol 'git@https'

       解决办法：采用git remote add origin http://github.com:yylxm/Git.git，Git.git是在github上创建的repositories 。

3、问题：执行$ git push -u origin master
                   出现问题 Username for 'https://github.com': yylxm
                                    To https://github.com/yylxm/YYXQZ.git
                                     ! [rejected]        master -> master (fetch first)
                                    error: failed to push some refs to 'https://github.com/yylxm/YYXQZ.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.

      解决办法：错误的主要原因是github中的README.md文件不在本地代码目录中，

                         可以通过如下命令进行代码合并【注：pull=fetch+merge】 git pull --rebase origin master

                         再通过命令git push -u origin master完成代码上传到github的操作。