1、read 读取键盘输入的变量

   read [-pt] variable

   -p   提示符

   -t   等待的秒数

   [root@bogon ~]# read -p "Please keyin your name:" -t 30 named
   Please keyin your name:zja
   [root@bogon ~]# echo $named
   zja

2、declare变量声明

   [root@bogon ~]# sum=100+300+50
   [root@bogon ~]# echo $sum
   100+300+50
   [root@bogon ~]# declare -i sum=100+300+50
   [root@bogon ~]# echo $sum
   450

3、数组

   [root@bogon ~]# var[1]="small min"
   [root@bogon ~]# var[2]="big min"
   [root@bogon ~]# var[3]="nice min"
   [root@bogon ~]# echo "${var[1]},${var[2]},${var[3]}"
   small min,big min,nice min

[root@bogon ~]# vbird="/home/vbird/testing/testing.x.sh"
[root@bogon ~]# echo ${vbird}
/home/vbird/testing/testing.x.sh
[root@bogon ~]# echo ${vbird%/*}
/home/vbird/testing

[root@bogon ~]# unset str; var=${str?novar}
-bash: str: novar
[root@bogon ~]# str="oldvar";var=${str?novar}
[root@bogon ~]# echo var="$var",str="$str"
var=oldvar,str=oldvar

设定：

[root@bogon ~]# lm
-bash: lm: command not found
[root@bogon ~]# alias lm='ls -al |more'
[root@bogon ~]# lm
total 252
drwxr-x--- 15 root root  4096 Mar 18 07:04 .
drwxr-xr-x 23 root root  4096 Mar 22 03:58 ..
-rw-------  1 root root   944 Mar 15 03:07 anaconda-ks.cfg
-rw-------  1 root root   530 Mar 18 07:04 .bash_history

...................................

查看都有哪些命令别名： 

[root@bogon ~]# alias
alias cp='cp -i'
alias l.='ls -d .* --color=tty'
alias ll='ls -l --color=tty'

清除别名：

unalias