一、系统快捷键
设置
键盘--查看
shift+ctrl +print 区域截图至剪切版
ctrl+alt+箭头 切换工作区
自定义打开终端快捷键
设置-》键盘-》自定义：名称：打开终端；命令：/usr/bin/gnome-terminal；点击编辑设置快捷键，如：ctrl+e 只要不冲突即可。
二、修改Host
vi /etc/hosts
添加一行
127.0.0.1 test.r.com
/etc/rc.d/init.d/network restart
三、几种查看CentOS系统版本和位数的方法查看系统版本：
cat /etc/redhat-release
CentOS Linux release 7.4.1708 (Core)
cat /proc/version
Linux version 3.10.0-693.5.2.el7.x86_64
(builder@kbuilder.dev.centos.org) (gcc version 4.8.5 20150623 (Red Hat
4.8.5-16) (GCC) ) #1 SMP Fri Oct 20 20:32:50 UTC 2017
uname -a
Linux localhost.localdomain 3.10.0-693.5.2.el7.x86_64 #1 SMP Fri Oct 20 20:32:50 UTC 2017 x86_64 x86_64 x86_64 GNU/Linux
cat /etc/issue
\S
Kernel \r on an \m
查看64位还是32位：
getconf LONG_BIT
64
file /bin/ls
/bin/ls: ELF 64-bit LSB executable, x86-64, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.6.32, BuildID[sha1]=3d705971a4c4544545cb78fd890d27bf792af6d4, stripped