Security

Security is the most important thing we should take care at first.

Change password

The first thing you login into your VPS using root is to change your root password your VPS provider gave. Run the passwd to change your root password.

After you run this command, your terminal will prompt you to input new password. So just type your new password twice. Linux will check your new password to prevent simple password or short password. So don’t use any exist words or any password only contains number.

Create a new User

One of the most important security thing is try your best not to login to your VPS using root account. A better way is to create a new user account and do anything you like as this new user.

Following command is to create a new user and set a password for this user. Please replace einverne as your own name.

# create a new user called einverne
adduser einverne
# set password for user einverne
passwd einverne

After you create a new user account successfully, we give the new user root privileges. Someone may be curious about why we create a new user and grant root privileges, so why don’t we just use root account. There are two points. One is that this can prevent user making system-destroying mistakes, second is that all command run by sudo will have a record in /var/log/secure which can be reviewed later if needed.

update default editor

apt install vim -y
update-alternatives --config editor

choose: vim

sudo

Run visudo command to enter sudo config file. Find a section called user privilege specification. And add a new line under this section like this:

# User privilege specification
root    ALL=(ALL)       ALL
# new add
einverne	ALL=(ALL)	NOPASSWD:ALL

ssh configuration

Now it’s time to make the server more secure. You can set the ssh configuration to permit root login. But before doing this config, please make sure to have a new account have the root privileges.

Edit ssh config file:

 sudo vim /etc/ssh/sshd_config

Then change follow line:

Port 22
PermitRootLogin no

Port means the ssh port you can connect, you can set any number between 1025 and 65535. PermitRootLogin means you can disallow root login, if you set to no.

Finally, add AllowUsers einverne at the bottom of the sshd_config file.

Then reload the config file to make ssh work.

service ssh reload

To test the new ssh config, do not logout of root. Open a new terminal and login with your new account like:

ssh -p port einverne@server.address

After you set up server ssh, you can generate SSH key at local computer and use SSH key to connect to server rather than using password. Generating a key at local computer:

ssh-keygen -t ed25519 -C "your@email.com"

follow the instruction of this command, for example you name it vps , just enter to skip password of key, and you will get two files under ~/.ssh/, vps is your private key, keep it safe. And vps.pub is the public key. And Now use ssh-copy-id to copy public key to server.

ssh-copy-id user@server.address

Then type the password. And it will be the last time to type your password to connect to server. If your computer don’t have the command ssh-copy-id, you have to copy the public key to server ~/.ssh/authorized_keys manually.

scp ~/.ssh/name.pub user@server:~/.ssh/

Then copy the file content to authorized_keys file.

cat name.pub >> authorized_keys

Finally to check the permission of the folder .ssh and file authorized_keys

drwx------ 2 einverne einverne       4096 Apr 19 21:25 .ssh
-rw------- 1 einverne einverne  744 Apr 19 21:14 authorized_keys

and if not:

chmod 700 ~/.ssh/
chmod 600 authorized_keys

setup alias

Add alias to .bashrc or .zshrc file.

alias vps = "ssh username@server -p port"

Then next time, you can just type vps to connect to server.

ssh config

There are two config file to setup ssh. One is system wide configuration file which can be found /etc/ssh/ssh_config. And another is per-user configuration file which is located under user home directory ~/.ssh/config. Most time we only care about user config.

Try to set up:

Host ds #this can be anything just a alias
	HostName server
	Port 22
	User username

Then we can use ssh ds to connect to server. If you have multi config just add to following like:

Host ds
	HostName server
	Port 22
	User einverne

Host github
	HostName github.com
	Port 22
	User einverne
	IdentityFile ~/.ssh/private_key_name

After all this, you can type following command to have a try:

scp filename ds:~/filename   # copy file to server
ssh ds "ls ~" 		# list server files

setup hostname

hostnamectl set-hostname example_hostname

setup timezone

设置时区：

sudo dpkg-reconfigure tzdata

Test VPS

单独总结了一篇文章来讲如何测评一个 VPS 性能。

Network test

You can use this solution to solve the problem. Or there are some download test file.

Install speedtest package:

pip install speedtest-cli

or

easy_install speedtest-cli

Usage:

$ speedtest-cli -h
usage: speedtest-cli [-h] [--bytes] [--share] [--simple] [--list]
                     [--server SERVER] [--mini MINI] [--source SOURCE]
                     [--timeout TIMEOUT] [--secure] [--version]

Command line interface for testing internet bandwidth using speedtest.net.
--------------------------------------------------------------------------
https://github.com/sivel/speedtest-cli

optional arguments:
  -h, --help         show this help message and exit
  --bytes            Display values in bytes instead of bits. Does not affect
                     the image generated by --share
  --share            Generate and provide a URL to the speedtest.net share
                     results image
  --simple           Suppress verbose output, only show basic information
  --list             Display a list of speedtest.net servers sorted by
                     distance
  --server SERVER    Specify a server ID to test against
  --mini MINI        URL of the Speedtest Mini server
  --source SOURCE    Source IP address to bind to
  --timeout TIMEOUT  HTTP timeout in seconds. Default 10
  --secure           Use HTTPS instead of HTTP when communicating with
                     speedtest.net operated servers
  --version          Show the version number and exit

一些机房 100M 测速下载文件地址，用于测速之用

description: VPS 的网络性能，主要分出口和入口二个指标，入口可以用 wget 文件得到。 看下载速度，如果是 11M/s，大概就是百兆口，70M/S，大概就是 G 口。 您的 VPS 搭建好网站环境后，可以用其它的 VPS 去拽这个文件，得到出口的带宽。

Directspace 机房 /10M.100M 测试包 Portland

wget http://bandwidth.directspace.net/10MBtest.zip
wget http://bandwidth.directspace.net/100MBtest.zip

Change default shell

sudo apt install zsh
chsh -s $(which zsh)

logout and login again.

BBR

BBR 是 Google 提出的 TCP拥塞控制算法，可以使Linux服务器显著地提高吞吐量和减少TCP连接的延迟，已经提交并合并到了 Linux 内核。

检查是否开启了 BBR：

sudo sysctl net.ipv4.tcp_available_congestion_control | grep bbr
sudo sysctl net.ipv4.tcp_congestion_control | grep bbr

如果开启通常会在结果中包含 bbr。如果没有开启则使用 Teddysun 的一键脚本，注意开启之后需要重启才能生效。

wget --no-check-certificate https://github.com/teddysun/across/raw/master/bbr.sh && chmod +x bbr.sh && ./bbr.sh

docker

Docker become much powerful these days, I can build and sever all my self-host services by using Docker.

sudo apt update
sudo apt install apt-transport-https ca-certificates curl software-properties-common
curl -fsSL https://download.docker.com/linux/ubuntu/gpg | sudo apt-key add -
sudo add-apt-repository "deb [arch=amd64] https://download.docker.com/linux/ubuntu bionic stable"
sudo apt update
apt-cache policy docker-ce
sudo apt install docker-ce
sudo systemctl status docker

或者通过一键脚本：

curl -fsSL https://get.docker.com/ | sh
# 启动并设置开机自启docker
systemctl enable --now docker

Executing the docker command without sudo 非 root 用户执行 docker 命令：

# sudo groupadd docker
sudo usermod -aG docker $USER
newgrp docker

设置后登出，然后登录。

安装 docker-compose

sudo curl -L "https://github.com/docker/compose/releases/download/1.27.4/docker-compose-$(uname -s)-$(uname -m)" -o /usr/local/bin/docker-compose
sudo chmod +x /usr/local/bin/docker-compose
# 如果/usr/local/bin不在PATH里
sudo ln -s /usr/local/bin/docker-compose /usr/bin/docker-compose

如果使用我的 dotfiles 配置，在 ~/.zshrc 第一次配置的时候就会把 docker-compose 二进制文件拉下来。

shadowsocks

sock5 proxy.

• first install pip

    yum update && yum install python-setuptools
    easy_install pip
  

  or use command yum -y install python-pip to install pip

• install shadowsocks using pip

    pip install shadowsocks
  

  just run this command

• create json config file

    vim /etc/shadowsocks.json
  

  edit file as follow:

    {
        "server":"[ip]",
        "server_port":[port],
        "local_port":[port],
        "password":"[password]",
        "timeout":600,
        "method":"AES-256-CFB"
    }
  

  Explanation of each field:

    - server: your hostname or server IP (IPv4/IPv6).
    - server_port: server port number.
    - local_port: local port number.
    - password: a password used to encrypt transfer.
    - timeout: connections timeout in seconds.
    - method: encryption method, "bf-cfb", "aes-256-cfb", "des-cfb", "rc4", etc. Default is table, which is not secure. "aes-256-cfb" is recommended.
  

• start server

  ssserver -c [json_path] -d start

  start service

lnmp

Second thing is to install lnmp, if you want to host a website on your VPS. You can use screen to install lnmp.

Screen can prevent network connection error during the lnmp installation. You can find more details on the lnmp official site

1. install screen
2. run this command: screen -S lamp to create a screen session
3. download packages wget -c http://soft.vpser.net/lnmp/lnmp1.1-full.tar.gz
4. uncompress the package tar zxf lnmp1.1-full.tar.gz
5. enter directory: cd lnmp1.1-full/
6. install lnmp If you are using Centos run ./centos.sh , If you are using Debian run ./debian.sh , If you are using Ubuntu run `./ubuntu.sh

If you’re ssh connection suddenly failed, you can connect to your server. Then run command screen -r lnmpto restore your lnmp installation.

From:http://www.vpser.net/manage/run-screen-lnmp.html

After installation, you will see some short instructions.

lnmp status manage: /root/lnmp {start|stop|reload|restart|kill|status}
default mysql root password:12345678
phpinfo : http://yourIP/phpinfo.php
phpMyAdmin : http://yourIP/phpmyadmin/
Prober : http://yourIP/p.php
Add VirtualHost : /root/vhost.sh

The path of some dirs:
mysql dir: /usr/local/mysql
php dir: /usr/local/php
nginx dir: /usr/local/nginx
web dir : /home/wwwroot/default

LNMP is a tool to auto-compile & install Nginx+MySQL+PHP on Linux
This script is a tool to Manage status of lnmp
For more information please visit http://www.lnmp.org

Usage: /root/lnmp {start|stop|reload|restart|kill|status}

reference

• http://linux.die.net/man/1/ssh-copy-id
• http://nerderati.com/2011/03/17/simplify-your-life-with-an-ssh-config-file/
• http://linux.die.net/man/5/ssh_config
• http://dhq.me/use-ssh-config-manage-ssh-session
• http://blog.jobbole.com/33790/

说是N6的Tips，当然里面很多都是Android 6.0 隐藏的功能。只要是原生 6.0 的系统都能够开启。

双击唤醒

Nexus 6 double tap to wake, root 之后安装一个app即可。

具体参考:xda-developers

开启状态栏电池百分比

原生 Android 6.0 有个小技巧能够开启状态栏的电池百分比，下拉通知栏，长按开启设置的齿轮，会打开Android 6.0 隐藏的设置，此时进入系统设置，会多出一个“System UI Tuner”，进入打开“Show embedded battery percentage”，则能在状态栏电池上显示百分比。

开启多窗口模式

另一个Android 6.0 隐藏功能，可能是官方并未完成对这个功能的开发和测试，但是就使用来看稳定性OK。开启过程如下，一句话就是修改 /system/build.prop。

1. 复杂来说，如果手机root过，用任何可以编辑 /system/build.prop 的app，类似下面链接中提到的 build.prop.editor，或者像我一样使用 Root Explorer，直接找到文件，打开文件找到”ro.build.type”一行，将原先的”user”值修改成为”userdebug”。保存之后重启手机。
2. 重启手机之后，进入设置，开发者选项，然后在 “drawing”设置下，开启多窗口模式。
3. 测试多窗口。点开多任务按钮应该能看到一个黑色的框。

具体参考:xda-developers

LED for Notifications

需要第三方kernel，可以根据以下教程自行刷入。

参考：xda-developers

几大常见的kernel：

1. Elementalx link
2. franco.Kernel link

unlock root recovery all in one

写给自己备忘：电源键+音量下可以进入recovery mode

详情参考:xda-developers

总结

最后总结一下N6的几个缺点：

1. 屏幕的问题，虽然是2K屏，但是 AMOLED 的屏幕黄屏问题始终存在
2. 待机时间，也就是耗电水平，正常使用一天是肯定没有问题的，当然重度用户是怎么也不会够的。不过N6的待机时间在同等水平的机子中也并不是很好的。
3. 不要使用涡轮快充来给手机充电，一些N6老用户使用涡轮充电给电池造成了伤害，导致手机电池膨胀，从而使得 N6 后壳开裂。

备忘

摩托罗拉官方网站显示Nexus 6将会有两个版本，分别是美国版的XT1103和国际版的XT1100，两者在基本硬件规格上大部分相同，只是支持的数据流模式和频谱略微有差别。美国版XT1103支持制式频段较少，国际版相对比较通用。

Americas Model (XT1103)
GSM/GPRS/EDGE (850, 900, 1800, 1900 MHz)
CDMA (800, 1900, secondary 800 MHz)
WCDMA (1, 2, 4, 5, 8)
LTE (2, 3, 4, 5, 7, 12, 13, 17, 25, 26, 29, 41)
CA DL (B2-B13, B2-B17, B2-29, B4-B5, B4-B13, B4-B29)

Global Model (XT1100)
GSM/GPRS/EDGE (850, 900, 1800, 1900 MHz)
WCDMA (1, 2, 4, 5, 6, 8, 9, 19)
LTE (1, 3, 5, 7, 8, 9, 19, 20, 28, 41)
CA DL (B3-B5, B3-B8)

XT1100国际版联通3G WCDMA制式可以直接使用，4G LTE部分支持1、3、5、7、8、9、19、20、28、41这些频段，国内联通和电信主要采用FDD-LTE制式中的1、3、7频段，移动则是TD-LTE中的41频段，因此理论上两种制式都可以直接使用。当然理论上永远是理论，毕竟国内运营商具体每个地方用何种频段并不一定，购买前还需要考虑这个问题。

再详细说下：

移动用户：从频段上看无论国际版还是北美版都支持band41，可以接收移动2.6G的4G信号。但用起来肯定不爽，具体原因跟Nexus 5相同，因为移动目前用于广覆盖和室内分布的TDD频段是39和40，而Nexus 6不支持这两个频段。另外Nexus 6也不支持移动3G，导致其极有可能出现Nexus 5一样的情况，接打电话后需要手工调才能返回4G待机。

联通用户：应该无忧，无论国际版还是北美版都支持band3，也就是联通的4G主频段。另外和Nexus 5一样，Nexus 6肯定也是完美支持CSFB语音回落，所以4G会用的很爽。不过话说回来，Nexus 6有的这些东西，Nexus 5国际版同样也有。

电信用户：总的来说，Nexus 6比Nexus 5强，至少在网络支持方面。如果可以接受Nexus 6的6寸巨屏。电信主力4G频段band3，两个版本的Nexus 6都支持，但仅有北美版支持CDMA，因此电信用户只能选择北美版。不过有一点要注意，电信在很多城市还用band1部署了4G，而北美版沿袭了摩托罗拉一贯的鸟样，对于美国本土不用的频段一律不支持，这次竟然连Nexus 5都支持的band1都删了。这样的后果就是，Nexus 6在未来用电信4G时，由于接收不到band1，可能网速会不如其他国内机子。不过亮点是，这次Nexus 6北美版支持Verizon的网络，这意味着，Nexus 5在电信网络上无法实现的CDMA语音回落，在Nexus 6上有99.999999%的可能会完美解决。因为Verizon与电信相同，其4G语音回落方案是：iPhone采用srlte，其他机型svlte。Nexus 5之所以没办法实现电信4G回落，是因为电信没有在基站侧部署1x CSFB，而1x CSFB是美帝Sprint支持的FDD－CDMA语音回落方案。

摘录自:机友会

期待了半年的《火星救援》并没有让我感到失望。

写在观影之前

早在今年6月份看到一段预告片之后就将这部电影加入了待看片单，等了半年，在好莱坞大片云集的11月，也没有去看任何影片只等着这一部。马特达蒙，最喜欢的演员，星际宇宙，最喜欢的题材，有这这样的组合怎能不让人期待。

写在观影之后

终于在等了半年之后，在25号看了0点场，电影没有让我失望，当然带来的感动和震撼也并没有超出想象。或许是《地心引力》和《星际穿越》的铺垫，让我对此类讲述宇宙的电影有了最基本的感受，宇宙浩瀚的视觉体验，飞船对接的惊险，以及人类在广袤宇宙的渺小。

这部电影的剧情其实很简单，如果稍微做过一些了解，看电影之前应该就能预料到电影中发生的事情，而正是对于这样一部电影，我更加期待的是导演和演员如何在故事剧情整体都被观众了解的情况下去推动剧情的发展。这部电影由Andy Weir小说改编，虽然没有看过小说，但是经过小说的验证，剧情并不会离谱到哪里，所以在看完这部电影之后对整个剧情的设定，情节的发展都没有找到比较大的漏洞。电影基本在沿用两条线叙事，火星上马特达蒙的生存挑战，地球上的营救计划的展开，总体沿用这两条故事线，而中间也穿插了赫尔梅斯号飞船上的故事，到影片的结束，赫尔梅斯号上的故事线和马特达蒙的线合二为一。从剧情上来看，故事整体发展都很平淡，也像之前看到的一些评论说的那样，导演尽量的在克制并没有打温情牌，即使是在片尾才出现的爱情线，也只是淡淡的一笔带过，而主角的亲情戏也是一再的克制，犹记得其中的一个镜头就是马特坐在火星的高地上，镜头从背后绕到前面，而中间伴随着马特的遗言式的自白，这也是我唯一能够想到的提交亲情的戏份。而相比《星际穿越》中的亲情带来的感动，导演 [[Ridley Scott]] 一再的将电影的重心放到营救的整个过程中。

影片是和同学一同前去观看的，部分同学说故事发展太平淡，高潮不明显，其实这部片子的问题也是存在的，片子在极尽所能渲染出火星壮美的地貌的时候无意中拖慢的剧情。在开场火星风暴袭来快速的剧情推动之后，令人印象深刻的马特自救，种土豆之后故事发展就趋于平缓，用淡淡的叙事来铺开，当然最后我能感受到的高潮就是赫尔梅斯号去接马特的时候，这也是全片的最高潮，只是现在回想来，似乎感觉到来的太快，而结束的也太快。

再说到表演，这就不得不提到马特达蒙，几乎是用他一个人的演技支撑起了整部影片，早在《谍影重重》《天才雷普利》《心灵捕手》的时候就深深的喜欢上了这个个性演员，更让我震惊的是他曾经和本阿弗莱克凭借《心灵捕手》获取了奥斯卡最佳电影原创剧本奖，这样一位实力派的演员竟然能够在剧本创作上获得如此殊荣更让我对他刮目相看。而在这部影片中的表现同样没有让人失望，我甚至觉得马特可以凭借这部电影去拼一下奥斯卡最佳男主，令人印象深刻地几场戏出现在开头的自救，在风暴过后，马特被天线击中，他有条不紊的从身体中取出天线的情节实在让人无法忘怀。另外在更多的自白中自然地表现出那种自娱自乐的精神，也只有马特能够表现出来。像很多人说的那样，这就是一部靠马特自救和段子组成的电影。而说到配角，我竟然认出了《纸牌屋》中的那个死掉的记者，是纸牌屋中死掉了所以来拍电影了吗。然后那个黑人主管也看的眼熟却也无法想起在哪里见到过。而赫尔梅斯号上得中尉是杰西卡·查斯坦，这位演员在当时《星际穿越》的时候认识了，但是因为这部戏中的戏份也并不是很多，只在开头很果断的决策和结尾营救马特的时候有些表现，而其他方面只能通过马特说的音乐品味太差来侧面描写一下，所以也看不出演技的好坏。不过让我印象深刻的倒是那个呆萌呆萌的天体物理学家，虽然出场时间也并不是很多，但是却让人眼前一亮，并为之会心一笑。从第一个躺在床上的镜头，到后来开“爱隆会议”，他的表现非常的高效到位。他把那种科学家的自信气质和学术范儿用一种诙谐的方式表现出来，而他的方案也是整个拯救计划中很重要的部分。

在说到娱乐性，对我来说，娱乐性对于这部电影来说应该就算是话题效应了，如果从今年6月份算起，我已经期待这部电影超过了5个月了。对我来说，娱乐性的体现已经足够充分，而在11月份，好莱坞电影集中上映的前提下，我相信《火星救援》也还是依然能够保证充足的话题性。而从另一方面，电影创造出的火星场景来看，也足够具有话题性，从《地心引力》创造的宇宙世界观，《星际穿越》创造的黑洞，好莱坞几乎在以一年一部的速度刷新着我们的宇宙观。而今年几乎是 NASA 的新世纪元年，就在《火星救援》美上映的前几天，NASA 宣布火星发现水，这简直就是给这部影片一个巨大的广告宣传，再到 NASA 今年公布的冥王星的图片，整个世界都被宇宙震撼到了。

最后在豆瓣上我会给剧情8分，表演8分，娱乐性9分。当然这都是带有私心的评分~(≧▽≦)/~啦啦啦。

电影删减

国内版删去马特达蒙光屁股一段戏。其实这里不得不吐槽一下，很多电影比这个过分的要更多，难道广电只是想刷一下存在感吗？什么都插手一脚却也并没有什么用。可是下面才是我想说的，在我告诉周围人这个删减的时候，周围人竟然说删得好，至于为什么删得好，我是无法理解的，当更重要的是或许是很多人以及习惯了这种删减的日子了吧。

写在看书之后

书里解答了我很多观影之后的疑问，帆布的疑惑，栖息仓中的爆炸等等，还有关于火星上大气的气压等等。

当然在电影过后看书的一大缺点就是在看到角色名字的时候不知不觉会在脑海里浮想起电影中的面孔，所以在看大部分沃特尼的自述的时候会想起马特达蒙。不过对我还好，我能记住的演员也就是赫尔梅斯上得几个航天员。当然下面我还要说，其实书中对这些角色的描写我觉得更成功，甚至从几句对白中表现出来的感觉抵得上电影中的画面和情节。

电影对书中内容的改编：

1. 两辆漫游车 书中对于漫游车的改造远远超出电影中的描述，沃特尼花费了大量的时间去改造漫游车，而这部分情节在电影上被省去了，或许是从电影表现来看并不是最佳的情节。在电影后半段时期，火星上的交代变少，更多的是展现火星神奇的地貌，而书中反而不是这样，在漫游车改造的过程中，沃特尼失去了地球的联络，只能依靠自己的知识改造漫游车。并且在之后的移动过程中是没有和 NASA 的联络的。

2. 电影中删减了很多沃特尼去往3000+公里外的 MAV 的情节 这也是在上面说到的一点，沃特尼在前往 MAV 的过程中没有人去协助，只依靠自己的努力，小说中甚至描述了他遭遇火星沙尘暴的情节，而在电影中几乎完全没有被提及，这也导致我在观影中感受到的电影中后段故事趋于平缓，当然这可能也是为了缩减电影时长而不得已为之，但是这一段沃特尼自救的部分真是惊心动魄，既紧张又充满刺激，当然在我为沃特尼这种临危不乱的精神敬佩的时候，沃特尼用自己的聪明才智已经快到达目的地了。

3. 小说中对配角形象的塑造更加成功 这里我不得不说，小说对这些配角的形象塑造更加生动。小说中在赫尔梅斯上得情节描述较电影多，而小说对地面 NASA 等的描述较小说少，所以从小说中能看到诙谐幽默，时常开玩笑的马丁尼兹，能看到指挥果断地刘易斯指挥官，还有搞办公室恋爱的约翰森，他们的形象，加上之前在电影中留下的记忆，共同组成他们成为一个角色的特征。

4. 对指挥官刘易斯的改编 看过电影的人应该都知道，最后是指挥官刘易斯去营救的沃特尼，其实当时看完电影并没有感觉到什么不适，但是后来想一想，虽然航天员什么方面都会训练一下，但是指挥官并没有什么特殊的理由让自己代替另一个专业航天员去营救沃特尼，当然这也可能是电影剧本的要求吧，因为我对那个人也真没多少印象，赫尔梅斯上一共六个人，上面提到的3个加上沃特尼，剩下的两个实在是没什么印象了，所以在最后电影中换成指挥官也情有可原吧。

和其他 Version Control System 一样，git 也有方法来触发自定义脚本。

两类 hooks：

• client hooks
• server hooks

Installing a hook

hook 脚本在 hooks 子目录下，大部分是 .git/hooks 下。在使用 git init 之后就会初始化一些 sample 脚本，在 hooks 下都以 .sample 结尾，如果要使用则需要将 .sample 后缀去掉。

Client-side Hooks

pre-commit

pre-commit hook 会在输入 commit message 之前被执行。

通常可以在该 hook 中检查代码是否被提交，运行 test，代码格式检查，或者其他 lint 工具检查。如果脚本返回 non-zero 值会阻断 commit。

prepare-commit-msg

prepare-commit-msg hook 会在 commit message 编辑器被调用前，在默认 message 被创建后被触发。这可以使得你可以自定义默认 message。这个 hook 接受一些参数：

• commit message 的文件路径
• commit 类型
• 如果是 amended 提交则包含 commit SHA-1

commit-msg

commit-msg hook 接受一个参数，可以在该 hook 中检查 commit message。

post-commit

在整个 commit 结束后， post-commit hook 会执行。不接受任何参数。通常该 hook 用来发送一些通知。

Other Hooks

Server-Side Hooks

reference

• https://git-scm.com/book/en/v2/Customizing-Git-Git-Hooks

在 java 中 try catch 的时候，大多数情况下是使用的 Exception，但是今天看代码有些却 catch 了 Throwable，于是总结下。

看 JDK 源码知道 Throwable 是 Exception 的超类，也同样是 Error 的超类，所以可想而知，如果 catch 了 Throwable，那么会连同 Exception 和 Error 一同 catch，这样也不会丢异常。

• Throwable 是所有异常的根，java.lang.Throwable
• Error 是错误，java.lang.Error，Error 通常是不可恢复的错误
• Exception 是异常，java.lang.Exception，Exception 通常是程序可恢复的

当程序发生不可控错误，抛出 Error 错误，与异常不同的是 Error 及其子类对象不应该被抛出。通常发生 Error 时需要介入处理。

reference

• https://stackoverflow.com/q/2274102/1820217

功能比较强大，比较重要的几个 Plugin 都在单独的文章中做了介绍，这里单独的列举一些特定场景使用的插件，带有语法高亮等的插件，比如针对 Nginx 配置， Dockerfile 文件等等的插件。

Plugins

优化 nginx 配置

Plug 'chr4/nginx.vim'

Language Related

Python

Go

Plug 'fatih/vim-go'

js

Plug 'kchmck/vim-coffee-script'
" CoffeeScript
Plugin 'mtscout6/vim-cjsx'

vimawesome

• https://vimawesome.com/

tr 是 translate 的缩写。

tr [OPTION] SET1 [SET2]

translate SET1 to SET2

转换大小写

cat "abc" | tr a-z A-Z
cat "abc" | tr [:lower:] [:upper:]

将空白转换成 TABs

echo "a b" | tr [:space:] '\t'

转换括号

echo ‘{abc}’ | tr ‘{}’ ‘()’ (abc)

delete set

删除 -d 指定的字符集

echo "abc" | tr -d 'a'
bc

删除数字

➜ echo "123abc123" | tr -d [:digit:]
abc

删除连续空白

➜ echo "emmmmmmmmmm   no" | tr -s [:space:] ' '
emmmmmmmmmm no %

squeeze repeats

echo "abbbbccccbd"  | tr -s a-z A-Z
ABCBD

使用 -c 补足

比如说想要删除除了数字之外的内容

➜ echo "my id is 123" | tr -cd [:digit:]
123%

单独使用 -c 选项则表示将 不是 SET1 中的内容，替换为 SET2 中内容

➜ echo 'abc123' | tr -c [:digit:] x
xxx123x%

reference

• man tr

Install Lua in Linux

You can install lua in Linux Mint/Debian/Ubuntu.. You can find all verions of lua here.

wget http://www.lua.org/ftp/lua-5.3.1.tar.gz
tar zxf lua-5.3.1.tar.gz
cd lua-5.3.1
make linux test

Finally, if test have passed, then install lua into the right place by running sudo make install:

einverne@mint ~/Downloads/lua-5.3.1 $ sudo make install
[sudo] password for einverne:
cd src && mkdir -p /usr/local/bin /usr/local/include /usr/local/lib /usr/local/man/man1 /usr/local/share/lua/5.3 /usr/local/lib/lua/5.3
cd src && install -p -m 0755 lua luac /usr/local/bin
cd src && install -p -m 0644 lua.h luaconf.h lualib.h lauxlib.h lua.hpp /usr/local/include
cd src && install -p -m 0644 liblua.a /usr/local/lib
cd doc && install -p -m 0644 lua.1 luac.1 /usr/local/man/man1

According to the output, we know that lua header files are located under /usr/local/include. And liblua.a lib is located under /usr/local/lib. This two paths may be used later when coding with C/C++. And most important thing executalbe file is located under /usr/local/bin. Most of the Linux distributions are installed lua by default. But most of them don’t have liblua.a installed.

Install Lua on Mac OS X

If you want to build from source code like under linux, just change make linux test into make macosx test. And all the following steps are the same as I mentioned in the Linux section.

If you want a more convenient way to install lua, you can download binary package here. And click next and next to finish installation.Default installation path is same as in Linux.

And id you are using Homebrew just run brew install lua, everything is done.

And you can find more ways to install lua on lua-users.org

For other OS

please see: http://lua-users.org/wiki/LuaDistributions

Testing Lua

After installation , run lua -v to check the lua version. Test lua by printing “hello world” using following code. Run lua in terminal:

einverne@mint ~ $ lua
Lua 5.3.1  Copyright (C) 1994-2015 Lua.org, PUC-Rio
> print "hello world"
hello world

Type Control+D to exit.

lua IDE

If you want to find a lua IDE, I highly recommend Zerobrane Studio. It is cross-platform and support different versions of lua from 5.1 to lastest 5.3. And it has a debugger build-in, which is great for debug lua code from local or remote. It is worth to have a try.

I have changed my desktop environment to Linux, and after I tried Ubuntu and Debian, I finally choose the Linux Mint distribution. I think there are some reasons why this distribution take the first place in distrowatch. User-friendly desktop environment and convenient software package manager make me very comfortable. Cause it is based on the Debian and Ubuntu, most of the applications are familiar.

Install a theme

The simplest way to install a new Cinnamon theme is with the Themes manager in System settings.

Go to System Settings -> Themes -> Get More Online -> Refresh list. You can choose Most Popular or Latest. The theme will be installed to your hidden folder ~/.themes

Dark Blue Glass

I highly recommend my modified Dark Blue Glass theme link. It is a mix of Dark Glass and mint numix blue theme. Or you can find more themes on the following sites:

• Themes (this is the official linux mint theme sites which you can directly download this themes and install in your cinnamon desktop environment):https://cinnamon-spices.linuxmint.com/themes
• Mint Numix Blue:https://cinnamon-spices.linuxmint.com/themes/view/434
• Dark Glass link:http://gnome-look.org/content/show.php/Dark+Glass?content=171257
• Numix Cinnamon Blue:http://cinnamon-spices.linuxmint.com/themes/view/196
• Noobslab themes and icons:http://www.noobslab.com/p/themes-icons.html
• Numix project:https://numixproject.org/ and PPA for numix project

icons

You can install a new icon set in two ways. One is by adding a PPA. You add the PPA, install the icon set. But you won’t find icon sets for all the icon themes. Therefore, the other way round is to download the compressed file and extract it to ~/.icons or ~/.local/share/icon . If this directory doesn’t exist, create one using the following command:

mkdir ~/.icons

The icons extracted in the above directory will be available for the current user only. If you want the icons to be available for all the users, you should extract the icons to /usr/share/icons .

Now, once you have installed the icon set, you can use a Unity Tweak Tool to change the icon theme. Use the following command to install Unity Tweak Tool:

sudo apt-get install unity-tweak-tool

Or in Linux mint you can just change icons under setting -> theme -> icons.

I highly recommend this one: papirus icons

sudo add-apt-repository ppa:varlesh-l/papirus-pack
sudo apt update
sudo apt install papirus-icons

• papirus suite:https://github.com/varlesh/papirus-suite
• link:https://launchpad.net/~varlesh-l/+archive/ubuntu/papirus-pack
• Ioncs:http://www.noobslab.com/p/themes-icons.html
• PPA:https://launchpad.net/~noobslab/+archive/ubuntu/icons/

Software Sources

You didn’t need to edit/etc/apt/sources.list and files under /etc/apt/sources.list.d/ mannually. All customs can be changed through UI. Just click “start menu” and choose the “Software Sources”. And this application can even custom the PPAs.

Necessary applications

Chrome

First is web browser, and of course Chrome. I am crazy about Google, and all Google related things. I have used Chrome since year 2011, after I am tried of the Firefox’s slowness. Although Firefox become more and more light, faster this years, I get used to Chrome. And what Chrome done makes me really happy. First thing is the bookmark and extension etc sync. I can reach all of my staff and customizations, after I login into my account. I don’t even need to worry about anything. All my Apps, Extensions, Settings, Autofill informations, History, Themes, Bookmarks, Passwords, and even Open tabs always follow my account. I can reach my opening tab on desktop from my Android phone. I can reopen bookmarks on my home laptop, which I added in my laboratory computer. And I can open chrome://history page to check all current opening tags from signed-in devices, and even check the unread article in the opening tab on my phone and browser all my chrome history.

sogou input method

It is necessary to have an input method for typing Chinese which I speak. I choose the sogou input method, because it is easy to use and have a very Good word dictionary. Sogou input method is based on fcitx. In Linux mint setting panel, we have the Language setting, we can choose to install fcitx components.

More detail information can be found in this blog article.

Following can be done through user interface, no need to run. Pasting here only for reference.

sudo apt-get install fcitx fcitx-table-wubi-large fcitx-frontend-all fcitx-frontend-gtk2 fcitx-frontend-gtk3 fcitx-frontend-qt4 fcitx-config-gtk fcitx-ui-classic fcitx-module-kimpanel fcitx-module-dbus fcitx-libs-qt
sudo apt-get install fcitx fcitx-bin fcitx-config-common fcitx-config-gtk fcitx-data fcitx-frontend-all fcitx-module-cloudpinyin fcitx-module-dbus fcitx-module-kimpanel fcitx-module-x11 fcitx-modules fcitx-qimpanel-configtool

After installation, “start”, “Fcitx Configuration” can config the input method, just add “Sogou Pinyin” to the panel.

shadowsocks

Use to cross China’s great firewall. Don’t need to talk more.

 pip install shadowsocks # install command line tool

If pip is missing, install pip first.

PPA is for Ubuntu >= 14.04.

sudo add-apt-repository ppa:hzwhuang/ss-qt5
sudo apt-get update
sudo apt-get install shadowsocks-qt5

To install Qt version of shadowsocks. From:GitHub.

Hardware related

Nvidia driver

“System settings” , “Driver Manager”, choose the right latest driver and install. After installation, you will find Nvidia icon at the right-bottom corner. Double click the icon to open the setting panel. In order to save the battery , you can use Intel(Power Saving Mode) for most time. And if choose NVIDIA(Performance Mode) for high performance need.

hardinfo

Install hardinfo tool to check hardware information through GUI

 sudo apt-get install hardinfo

System tools

If there is no special instruction, all of the following applications can be installed from the Software Manager in Linux Mint.

gnome do

As it official introduction said “Do things as quickly as possible (but no quicker) with your files, bookmarks, applications, music, contacts, and more!”. I set a shortcut Alt+Space to launch Gnome do. And you can just type several keys to start any application quickly.

install following package:

• gnome-do
• gnome-do-plugins

guake

Use F12 to open a terminal. Dropdown terminal, you can right click the terminal after you press F12 to configure your guake.

PlayOnLinux

“PlayOnLinux is a front-end for wine. It permits you to easily install Windows Games and software on Linux. It is advised to have a functional internet connection.” I use playonlinux to install Evernote and cloudmusic(网易云音乐). Although I met a lot of problems during installation of Evernote. But finally evernote 5.8.x can be installed on wine 1.7.x.

There are several packages you need to install to make PlayOnLinux work.

• wine
• wine mono
• wine gecho
• ttf-mscorefonts-installer

Tools

Most of the following can be installed from default Software Manager. Just type name of the application and search then click install.

网易云音乐

cloud music client and my favourite music client. Here is the link to it’s official site, where you can found clients for all platforms include linux.

Evernote

my favourite cloud notebook with a very clean Android client.

shutter

Linux mint 17 has a default screenshot software called Screenshot. It is a very simple screenshot software. Shutter is more powerful.

Dropbox

Sync all my files. When I installed Dropbox through it’s offical installer, there was a problem I cannot connect to Dropbox directly from China. Here is a solution to redirect connections to shadowsocks sock5 proxy. You should install proxychains.

sudo apt install proxychains
# config socks4 127.0.0.1 9050  To socks5 127.0.0.1 1080 which is the default of shadowsocks
vi /usr/local/etc/proxychains.conf
# then use proxychains to start dropbox
proxychains4 dropbox start -i

Then dropbox will start to start and install, then after installation you can set sock5 proxy in dropbox settings.

BCloud

Baidu pan linux port. It is really a great work. Thank the author.

You can download here

remmina

Remote desktop connection client able to display and control a remote desktop seesion. It supports multiple network protocols in an integrated and consistant user interface. Currently RDP, VNC, NX, XDMCP and SSH protocols are supported.

Gufw

linux firewall.

Calibre

E-book manager, 电子书管理. It is very efficient when you plug in kindle using USB port Calibre is prepare to serve.

WizNote

Evernote like cloud notebook client. Find more information here. You can install through PPA:

$ sudo add-apt-repository ppa:wiznote-team
$ sudo apt-get update
$ sudo apt-get install wiznote

SimpleScreenRecorder

one of the screenrecoders I use.

Picasa

Best image and picture manager ever from Google.

audacity audio editor

record and edit audio files

kdenlive video editor

non-linear video editing suite.

WPS Office for Linux

Office software include writer, spreadsheets and presentation.

KeePassX

Password manager. But I prefer LastPass.

youdao dict

This client really make me impressed. It is faster and simple than any other platform client. Launch it with Gnome do, and use it to check English word is a very happy work. Someone used to recommand me the StarDict, but I think youdao dict is a better choice for me.

Docky

Elegant, powerful, clean dock.

Or there is another choice Cairo Dock.

ntfs configuration tool

Install this tool using this command:

 sudo apt-get install ntfs-config

and you can find NTFS Configuration Tool in the menu. It is a very efficient tool to auto mount windows NTFS partitions. You can setup to auto-mount when your Linux mint start up. It is really useful if you have a second hard drive installed and you want it to auto-mount each time you restart your system.

smplayer or vlc

video player always need one. Personally, I like smplayer more.

Nuvola Player 3

You can follow the instruction on it’s official site. It was great, espcially when you want to listen to music at Google Play Music, or other cloud stream music. It support a lot of services, like Amazon Cloud Player, Play Music, Plex Music, Spotify, Tuneln, etc.

birdie

Birdie is beautiful Twitter client for GNU/Linux.

PPA (14.04) Birdie can be installed from our PPA, which provides automatic updates whenever we improve the application.

$ sudo add-apt-repository ppa:birdie-team/stable
$ sudo apt-get update
$ sudo apt-get install birdie

from it official site:http://www.birdieapp.eu

FFmpeg

all the detail information can be found at it’s official site.

$ sudo add-apt-repository ppa:mc3man/trusty-media
$ sudo apt-get update
$ sudo apt-get install ffmpeg

Teamviewer

Remote control application. I need it to help to connect my mac in lab and other Windows machine. You can download here. And because it is cross-platform. You can install in other OS and connect it easily.

Programming tools

vim

Use apt-get search vim to search related vim packages, you will find several packages,like vim-gtk, vim-gnome etc. Install vim and vim-gtk package to install vim and gvim. And config my vim with my dotfile, https://github.com/einverne/dotfiles.

git

best version control system. And I am using SmartGit.

SmartGit

Git GUI

Sublime Text

Text Editor. Later I found Atom which is also great.

haroopad

markdown editor.

eclipse with jdt and cdt

sometime need java and c++ IDE for test.

boost

install boost library from source using the following code:

 sudo apt-get install libboost-all-dev

all boost library is located at /usr/include/boost

Android Studio

Check official site for more information.

PyCharm

Python IDE

ZeroBrane Studio

Lua IDE

SQLiteman

Sqlite manager

Applets

Weather

You can have your local weather forecast in desktop.

Desktop Capture

Screenshot and screencasting tools which saves me a lot of time.

I have created a list in Youtube, you can check it for information.

Most of computer fonts people using are TrueType fonts. TrueType fonts end with .ttf, which stand for TrueType Font. This tutorial shows how to install TrueType fonts in Linux (Debian, Ubuntu, Linux Mint, etc).

Linux 字体文件夹

Linux 下默认安装的字体都被存放在 /usr/share/fonts 下。

如果是个人使用可以将字体文件拷贝到 ~/.fonts 目录中。所有支持的字体文件路径可以通过系统的 /etc/fonts/fonts.conf 文件查看到。

把字体文件拷贝到对应的目录之后，需要执行

# create an index of scalable font files for X
mkfontscale
# create an index of X font files in a directory
mkfontdir
fc-cache -fv

查看已安装字体

使用如下命令来查看已安装字体：

fc-list
# 查看中文字体
fc-list :lang=zh

General way to install TrueType fonts

All of the TrueType fonts are under /usr/share/fonts/truetype, simplest way is to copy ttf file to this directory and give it the right permission. For example, if you want to install Ubuntu font family manually. You can download the font file from official site.

In the terminal, download the package:

 wget http://font.ubuntu.com/download/ubuntu-font-family-0.80.zip

unzip the file into directory ubuntu-font-family-0.80

 unzip ubuntu-font-family-0.80.zip

and then use copy command to copy all the files to /usr/share/fonts/truetype,/usr/share/fonts directory and sub directory need root to write, so you should add sudo before command. The -r paramater represent recursive, it means all the files under ubuntu-font-family-0.80 will be copied to the right place.

 sudo cp -r ubuntu-font-family-0.80/ /usr/share/fonts/truetype/

finally, you shoulde give this directory and all the ttf under this directory right permission. All the new fonts now can only be used by root. We need to change the permission to let all the users to use these fonts:

 sudo chmod 755 /usr/share/fonts/truetype/ubuntu-font-family-0.80/ -R

then, refresh the font cache to let system detect these fonts:

 fc-cache -f -v

Install new fonts only for current user

As I mentioned in the first part, if you copy the ttf file to /usr/share/fonts directory, all the users can use these new fonts. But if you only want to provide these fonts to specific user, like current login user , you can just copy the file to ~/.fonts directory. If there is no such directory, just create it. The ~ stand for current user’s home directory, full path is /home/<username>. So repeat the operation to install Ubuntu font family:

mkdir ~/.fonts
cp -r ubuntu-font-family-0.80/ ~/.fonts/
fc-cache -fv

Install microsoft core fonts

Microsoft Core Fonts include these fonts:

• Andale Mono
• Arial Black
• Arial (Bold, Italic, Bold Italic)
• Comic Sans MS (Bold)
• Courier New (Bold, Italic, Bold Italic)
• Georgia (Bold, Italic, Bold Italic)
• Impact
• Times New Roman (Bold, Italic, Bold Italic)
• Trebuchet (Bold, Italic, Bold Italic)
• Verdana (Bold, Italic, Bold Italic)
• Webdings

Debian/Ubuntn/Linux Mint user just open terminal and run these command:

sudo apt-get install ttf-mscorefonts-installer

or Linux Mint user can find this package in the Software Manager, just search it and click install.

Install Chinese fonts

.ttf files are the English fonts, while .TTF files are Chinese fonts. If we check the C:\Windows\Fonts under Microsoft Windows, there are 3 kind of fonts. One is the .fon fonts, which is the DOS system font, and other two fonts are .ttf and .TTF. We can just make a copy of all .ttf and .TTF file and copy all the files to /usr/share/fonts/ directory under Linux. Although it is illegal under Microsoft’s TOC, but we can still do it. :)

If you dual boot your computer, mount the Windows and copy the files

sudo mkdir /usr/share/fonts/truetype/WindowsFonts
sudo cp -r /media/Windows/Fonts/*.ttf /usr/share/fonts/truetype/WindowsFonts/
sudo cp -r /media/Windows/Fonts/*.TTF /usr/share/fonts/truetype/WindowsFonts/

Install open source Chinese fonts, like 文泉驿 - 微米黑 文泉驿 - 正黑

sudo apt-get install ttf-wqy-microhei ttf-wqy-zenhei

several Chinese font we can choose:

• Google noto http://www.google.com/get/noto
• 文泉驿 http://wenq.org/

To check more about Chinese font visit Arch wiki

Tip

Install Software Manager under Linux Mint

Linux Mint user can find a font manager under Software Manager. It is really a cool tool to manager your fonts.

List all available fonts

fc-list is a quick and handy command to lists fonts and styles available on the system for applications using fontconfig. You can use fc-list to find out whether particular language font is installed or not.

To list all font faces:

$ fc-list

To lists font faces that cover Chinese language:

$ fc-list :lang=zh

Output will be all available Chinese fonts.

Fix WPS for Linux font missing error

After I installed WPS for Linux under Linux Mint 17.2, I met this problem, “系统缺失字体 symbol、wingdings、wingdings 2、wingdings 3、wedding”. According to the copyright, WPS for Linux doesn’t contains these five fonts. You can only find these five fonts and install them in the right place like I said before. One way to find these fonts is to find them in Microsoft Windows system. And another way is to download these files from Internet and install.

Install Korean fonts

Use following command to search Korean font

apt-cache search korean font

and use this command to install Korean font to linux:

sudo apt-get install fonts-unfonts-core fonts-unfonts-extra

常识

字体类型：

• Sans-serif 无衬线体 = 黑体：并不是具体一款字体，而是一类字体，选择它其实等于选择这类字体中优先级最高的那款字体。
• Serif 衬线体 = 白体：同上
• Monospace 等宽字体，意思是字符宽度相同：同上
• 点阵字体 位图字体

无衬线体更适合电脑屏幕阅读，衬线体适合打印。因为衬线可以使得人视线平齐于一行。也就是说不会读破行。

中文显示时有不同的方式，一方面因为中文本身拥有的横和同高度就可以导致这种平齐。行距对中文更重要。

For more information check Debian page Arch wiki and Ubuntu wiki