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https://github.com/dunwu/linux-tutorial.git
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57 lines
1.2 KiB
Bash
57 lines
1.2 KiB
Bash
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#!/usr/bin/env bash
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################### 声明变量 ###################
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name="world"
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echo "hello ${name}"
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# Output: hello world
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################### 输出变量 ###################
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folder=$(pwd)
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echo "current path: ${folder}"
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################### 只读变量 ###################
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rword="hello"
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echo ${rword}
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# Output: hello
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readonly rword
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# rword="bye" # 如果放开注释,执行时会报错
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################### 删除变量 ###################
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dword="hello" # 声明变量
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echo ${dword} # 输出变量值
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# Output: hello
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unset dword # 删除变量
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echo ${dword}
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# Output: (空)
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################### 系统变量 ###################
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echo "UID:$UID"
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echo LOGNAME:$LOGNAME
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echo User:$USER
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echo HOME:$HOME
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echo PATH:$PATH
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echo HOSTNAME:$HOSTNAME
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echo SHELL:$SHELL
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echo LANG:$LANG
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################### 自定义变量 ###################
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days=10
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user="admin"
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echo "$user logged in $days days age"
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days=5
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user="root"
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echo "$user logged in $days days age"
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# Output:
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# admin logged in 10 days age
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# root logged in 5 days age
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################### 从变量读取列表 ###################
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colors="Red Yellow Blue"
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colors=$colors" White Black"
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for color in $colors
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do
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echo " $color"
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done
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