1 下載github 上，主分支以外的其他分支
"checkout" the remote branch as a new local branch, and specify a new local branch name.
git checkout -b newlocalbranchname origin/branch-name
Or you can do:
git checkout -t origin/branch-name
The latter will create a branch that is also set to track the remote branch.
2 ubuntu下載android 源碼時，出現錯誤：Received HTTP code 503 from proxy after CONNECT
解決方案：
unset HTTP_PROXY unset HTTPS_PROXY git config --global --unset http.proxy git config --global --unset https.proxy git clone http://yourUser@stashAddress:stashPort/apptest.git
To define proxies again:
export HTTP_PROXY=proxyaddress:port export HTTPS_PROXY=proxyaddress:port git config --global http.proxy http://proxyaddress:port git config --global https.proxy http://proxyaddress:port
3 更改項目下所有分支：
repo start preview2 refs/tags/android-o-preview-2 --all
repo start oreo-cts-release remotes/aosp/oreo-cts-release --all
一次把所有project都切換到別的branch
repo forall -c git checkout [BRANCH_NAME]
４ 列出所有遠程分支tag
git ls-remote --tags
5 repo init 下載代碼時，503 error, and ping 8.8.8.8 or ping goole.com unknown host :
Edit
/etc/network/interfaces:sudo nano /etc/network/interfaces
Below
iface eth0 inet staticadd the following line:dns-nameservers 8.8.8.8 8.8.4.4
This will use Google's DNS servers.
Restart your network:
sudo /etc/init.d/networking restart
6 repo sync 下錯分支怎麼辦：
If you run repo init a second time with a different branch, you can simply repo sync and it will not download the entire source code again.
７ add git log to files: 保存git 提交log到文件中
git log --after="2017-6-30" > log_630.txt
參考：https://www.atlassian.com/git/tutorials/git-log
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