git branch//确认在master分支下  
*master  
git pull  
git rebase  
git add -u//遇到冲突，要解决，再执行...  
git rebase --continue  
...
over when arrive "master"//到master为止  

git clone git@git.abc.com:user/space/A.git //准备A库代码  
cd A  
git branch //确保在master分支下  
*master  

git remote add B git@git.abc.com:user/space/B.git //设置B库  
git fetch B  

git diff B/master //查看diff  

git fetch origin //更新A  
git merge origin/master (master = git pull)  

git merge B/master  //merge B to A  
git mergetool //有冲突解决掉  
git commit  //测试OK再commit  
git push origin master //Push合并更新到A库远端  

git clean -i: clean untracked files  
git remote //show branches  
git remote -v //show branches details  
git remote show B //show B info  
git reset --hard //rest to latest commit status
git stash //save eidit status, back to latest commit status