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