1199 lines
23 KiB
Markdown
1199 lines
23 KiB
Markdown
Bash 备忘清单
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===
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这是开始使用 linux bash shell 脚本的快速参考备忘单。
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入门
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-----
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### hello.sh
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```bash
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#!/bin/bash
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VAR="world"
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echo "Hello $VAR!" # => Hello world!
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```
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执行脚本
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```shell
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$ bash hello.sh
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```
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### 变量
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```bash
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NAME="John"
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echo ${NAME} # => John (变量)
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echo $NAME # => John (变量)
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echo "$NAME" # => John (变量)
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echo '$NAME' # => $NAME (字符串原样输出)
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echo "${NAME}!" # => John! (变量)
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NAME = "John" # => Error (注意不能有空格)
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```
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### 注释
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```shell
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# 这是一个内联 Bash 注释。
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: '
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这是一个
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非常整洁的
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bash 注释
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'
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```
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多行注释使用 `:'` 打开和 `'` 关闭
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### 参数
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<!--rehype:wrap-class=row-span-2-->
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表示 | 描述
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:-|-
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`$1` … `$9` | 参数 1 ... 9
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`$0` | 脚本本身的名称
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`$1` | 第一个参数
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`${10}` | 位置参数 10
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`$#` | 参数数量
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`$$` | shell 的进程 id
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`$*` | 所有参数
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`$@` | 所有参数，从第一个开始
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`$-` | 当前选项
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`$_` | 上一个命令的最后一个参数
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<!--rehype:className=left-align-->
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见：[特殊参数](http://wiki.bash-hackers.org/syntax/shellvars#special_parameters_and_shell_variables)
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### 函数
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```bash
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get_name() {
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echo "John"
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}
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echo "You are $(get_name)"
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```
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见：[函数](#bash-函数)
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### 条件句
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```bash
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if [[ -z "$string" ]]; then
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echo "String is empty"
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elif [[ -n "$string" ]]; then
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echo "String is not empty"
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fi
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```
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见：[条件句](#bash-条件句)
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### 大括号扩展
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```shell
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echo {A,B}.js
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```
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---
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表示 | 描述
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:-|-
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`{A,B}` | 与 `A B` 相同
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`{A,B}.js` | 与 `A.js B.js` 相同
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`{1..5}` | 与 `1 2 3 4 5` 相同
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见：[大括号扩展](http://wiki.bash-hackers.org/syntax/expansion/brace)
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### Shell 执行
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```bash
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# => I'm in /当前/的/路径
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echo "I'm in $(PWD)"
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# Same as:
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echo "I'm in `pwd`"
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```
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见：[命令替换](http://wiki.bash-hackers.org/syntax/expansion/cmdsubst)
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Bash 参数扩展
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-----
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### 语法
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<!--rehype:wrap-class=row-span-2-->
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代码 | 描述
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:-|-
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`${FOO%suffix}` | 删除后缀
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`${FOO#prefix}` | 删除前缀
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`${FOO%%suffix}` | 去掉长后缀
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`${FOO##prefix}` | 删除长前缀
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`${FOO/from/to}` | 替换第一个匹配项
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`${FOO//from/to}` | 全部替换
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`${FOO/%from/to}` | 替换后缀
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`${FOO/#from/to}` | 替换前缀
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#### 子字符串
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表示 | 描述
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:-|-
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`${FOO:0:3}` | 子串 _(位置，长度)_
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`${FOO:(-3):3}` | 从右边开始的子串
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#### Length
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表示 | 描述
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:-|-
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`${#FOO}` | `$FOO` 的长度
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#### 默认值
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表示 | 描述
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:-|-
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`${FOO:-val}` | `$FOO`，如果未设置，则为 `val`
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`${FOO:=val}` | 如果未设置，则将 `$FOO` 设置为 `val`
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`${FOO:+val}` | `val` 如果设置了`$FOO`
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`${FOO:?message}` | 如果 `$FOO` 未设置，则显示消息并退出
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<!--rehype:className=code-nowrap left-align-->
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### 替代 Substitution
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```bash
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echo ${food:-Cake} #=> $food or "Cake"
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```
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```bash
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STR="/path/to/foo.cpp"
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echo ${STR%.cpp} # /path/to/foo
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echo ${STR%.cpp}.o # /path/to/foo.o
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echo ${STR%/*} # /path/to
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echo ${STR##*.} # cpp (extension)
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echo ${STR##*/} # foo.cpp (basepath)
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echo ${STR#*/} # path/to/foo.cpp
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echo ${STR##*/} # foo.cpp
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echo ${STR/foo/bar} # /path/to/bar.cpp
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```
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### 切片 Slicing
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```bash
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name="John"
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echo ${name} # => John
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echo ${name:0:2} # => Jo
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echo ${name::2} # => Jo
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echo ${name::-1} # => Joh
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echo ${name:(-1)} # => n
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echo ${name:(-2)} # => hn
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echo ${name:(-2):2} # => hn
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length=2
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echo ${name:0:length} # => Jo
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```
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见：[参数扩展](http://wiki.bash-hackers.org/syntax/pe)
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### 基本路径和目录路径
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```bash
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SRC="/path/to/foo.cpp"
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```
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---
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```bash
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BASEPATH=${SRC##*/}
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echo $BASEPATH # => "foo.cpp"
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```
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---
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```bash
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DIRPATH=${SRC%$BASEPATH}
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echo $DIRPATH # => "/path/to/"
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```
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### 转换
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```bash
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STR="HELLO WORLD!"
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echo ${STR,} # => hELLO WORLD!
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echo ${STR,,} # => hello world!
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STR="hello world!"
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echo ${STR^} # => Hello world!
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echo ${STR^^} # => HELLO WORLD!
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ARR=(hello World)
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echo "${ARR[@],}" # => hello world
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echo "${ARR[@]^}" # => Hello World
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```
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Bash 数组
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------
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### 定义数组
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```bash
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Fruits=('Apple' 'Banana' 'Orange')
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Fruits[0]="Apple"
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Fruits[1]="Banana"
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Fruits[2]="Orange"
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ARRAY1=(foo{1..2}) # => foo1 foo2
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ARRAY2=({A..D}) # => A B C D
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# 合并 => foo1 foo2 A B C D
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ARRAY3=(${ARRAY1[@]} ${ARRAY2[@]})
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# 声明构造
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declare -a Numbers=(1 2 3)
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Numbers+=(4 5) # 附加 => 1 2 3 4 5
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```
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### 索引
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:- | -
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:- | -
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`${Fruits[0]}` | 第一个元素
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`${Fruits[-1]}` | 最后一个元素
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`${Fruits[*]}` | 所有元素
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`${Fruits[@]}` | 所有元素
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`${#Fruits[@]}` | 总数
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`${#Fruits}` | 第一节长度
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`${#Fruits[3]}` | 第n个长度
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`${Fruits[@]:3:2}` | 范围
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`${!Fruits[@]}` | 所有 Key
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### 迭代 Iteration
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```bash
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Fruits=('Apple' 'Banana' 'Orange')
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for e in "${Fruits[@]}"; do
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echo $e
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done
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```
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#### 有索引
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```bash
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for i in "${!Fruits[@]}"; do
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printf "%s\t%s\n" "$i" "${Fruits[$i]}"
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done
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```
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### 操作
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<!--rehype:wrap-class=col-span-2-->
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```bash
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Fruits=("${Fruits[@]}" "Watermelon") # 添加
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Fruits+=('Watermelon') # 也是添加
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Fruits=( ${Fruits[@]/Ap*/} ) # 通过正则表达式匹配删除
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unset Fruits[2] # 删除一项
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Fruits=("${Fruits[@]}") # 复制
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Fruits=("${Fruits[@]}" "${Veggies[@]}") # 连接
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lines=(`cat "logfile"`) # 从文件中读取
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```
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### 数组作为参数
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```bash
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function extract()
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{
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local -n myarray=$1
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local idx=$2
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echo "${myarray[$idx]}"
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}
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Fruits=('Apple' 'Banana' 'Orange')
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extract Fruits 2 # => Orangle
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```
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Bash 字典
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------------
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### 定义
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```bash
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declare -A sounds
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```
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```bash
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sounds[dog]="bark"
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sounds[cow]="moo"
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sounds[bird]="tweet"
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sounds[wolf]="howl"
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```
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### 使用字典
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```bash
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echo ${sounds[dog]} # Dog's sound
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echo ${sounds[@]} # All values
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echo ${!sounds[@]} # All keys
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echo ${#sounds[@]} # Number of elements
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unset sounds[dog] # Delete dog
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```
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### 迭代
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```bash
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for val in "${sounds[@]}"; do
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echo $val
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done
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```
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---
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```bash
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for key in "${!sounds[@]}"; do
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echo $key
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done
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```
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Bash 条件句
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------------
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### 整数条件
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条件 | 描述
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:- | -
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`[[ NUM -eq NUM ]]` | 等于 <yel>Eq</yel>ual
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`[[ NUM -ne NUM ]]` | 不等于 <yel>N</yel>ot <yel>e</yel>qual
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`[[ NUM -lt NUM ]]` | 小于 <yel>L</yel>ess <yel>t</yel>han
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`[[ NUM -le NUM ]]` | 小于等于 <yel>L</yel>ess than or <yel>e</yel>qual
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`[[ NUM -gt NUM ]]` | 大于 <yel>G</yel>reater <yel>t</yel>han
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`[[ NUM -ge NUM ]]` | 大于等于 <yel>G</yel>reater than or <yel>e</yel>qual
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`(( NUM < NUM ))` | 小于
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`(( NUM <= NUM ))` | 小于或等于
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`(( NUM > NUM ))` | 比...更大
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`(( NUM >= NUM ))` | 大于等于
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### 字符串条件
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条件 | 描述
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:- | -
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`[[ -z STR ]]` | 空字符串
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`[[ -n STR ]]` | <yel>非</yel>空字符串
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`[[ STR == STR ]]` | 相等
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`[[ STR = STR ]]` | 相等(同上)
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`[[ STR < STR ]]` | 小于 _(ASCII)_
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`[[ STR > STR ]]` | 大于 _(ASCII)_
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`[[ STR != STR ]]` | 不相等
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`[[ STR =~ STR ]]` | 正则表达式
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### 例子
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<!--rehype:wrap-class=row-span-3-->
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#### 字符串
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```bash
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if [[ -z "$string" ]]; then
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echo "String is empty"
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elif [[ -n "$string" ]]; then
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echo "String is not empty"
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else
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echo "This never happens"
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fi
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```
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#### 组合
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```bash
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if [[ X && Y ]]; then
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...
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fi
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```
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#### 相等
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```bash
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if [[ "$A" == "$B" ]]; then
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...
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fi
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```
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#### 正则表达式
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```bash
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if [[ '1. abc' =~ ([a-z]+) ]]; then
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echo ${BASH_REMATCH[1]}
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fi
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```
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#### 小于
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```bash
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if (( $a < $b )); then
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echo "$a is smaller than $b"
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fi
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```
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#### 存在
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```bash
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if [[ -e "file.txt" ]]; then
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echo "file exists"
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fi
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```
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### 文件条件
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<!--rehype:wrap-class=row-span-2-->
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条件 | 描述
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:- | -
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`[[ -e FILE ]]` | 存在
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`[[ -d FILE ]]` | 目录
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`[[ -f FILE ]]` | 文件
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`[[ -h FILE ]]` | 符号链接
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`[[ -s FILE ]]` | 大小 > 0 字节
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`[[ -r FILE ]]` | 可读
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`[[ -w FILE ]]` | 可写
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`[[ -x FILE ]]` | 可执行文件
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`[[ f1 -nt f2 ]]` | f1 比 f2 新
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`[[ f1 -ot f2 ]]` | f2 比 f1 新
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`[[ f1 -ef f2 ]]` | 相同的文件
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### 更多条件
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条件 | 描述
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:- | -
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`[[ -o noclobber ]]` | 如果启用 <pur>OPTION</pur>
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`[[ ! EXPR ]]` | 不是 <pur>Not</pur>
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`[[ X && Y ]]` | 和 <pur>And</pur>
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`[[ X \|\| Y ]]` | 或者 <pur>Or</pur>
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### 逻辑和，或
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```bash
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if [ "$1" = 'y' -a $2 -gt 0 ]; then
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echo "yes"
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fi
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if [ "$1" = 'n' -o $2 -lt 0 ]; then
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echo "no"
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fi
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```
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Bash 循环
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-----
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### 基本 for 循环
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```bash
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for i in /etc/rc.*; do
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echo $i
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done
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```
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### 类似 C 的 for 循环
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```bash
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for ((i = 0 ; i < 100 ; i++)); do
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echo $i
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done
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```
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### 范围
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<!--rehype:wrap-class=row-span-2-->
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|
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```bash
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for i in {1..5}; do
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echo "Welcome $i"
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done
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```
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#### 步长
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```bash
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for i in {5..50..5}; do
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echo "Welcome $i"
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done
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```
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### 自动递增
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```bash
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i=1
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while [[ $i -lt 4 ]]; do
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echo "Number: $i"
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((i++))
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done
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```
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### 自动递减
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```bash
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i=3
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while [[ $i -gt 0 ]]; do
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echo "Number: $i"
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((i--))
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done
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```
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### Continue
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||
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```bash {data=3,5}
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for number in $(seq 1 3); do
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if [[ $number == 2 ]]; then
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continue;
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fi
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echo "$number"
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done
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```
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### Break
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```bash
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for number in $(seq 1 3); do
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if [[ $number == 2 ]]; then
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# 跳过整个循环的其余部分。
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break;
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fi
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# 这只会打印 1
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echo "$number"
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done
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```
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### Until
|
||
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||
```bash
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count=0
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||
until [ $count -gt 10 ]; do
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||
echo "$count"
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((count++))
|
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done
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```
|
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### 死循环
|
||
|
||
```bash
|
||
while true; do
|
||
# 下面是一些代码
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||
done
|
||
```
|
||
|
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### 死循环(简写)
|
||
|
||
```bash
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||
while :; do
|
||
# 下面是一些代码
|
||
done
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||
```
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||
|
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### 读取文件的每一行
|
||
|
||
```bash
|
||
cat file.txt | while read line; do
|
||
echo $line
|
||
done
|
||
```
|
||
|
||
Bash 函数
|
||
---------
|
||
|
||
### 定义函数
|
||
|
||
```bash
|
||
myfunc() {
|
||
echo "hello $1"
|
||
}
|
||
```
|
||
|
||
同上(替代语法)
|
||
|
||
```bash
|
||
function myfunc() {
|
||
echo "hello $1"
|
||
}
|
||
```
|
||
|
||
```bash
|
||
myfunc "John"
|
||
```
|
||
|
||
### 返回值
|
||
|
||
```bash
|
||
myfunc() {
|
||
local myresult='some value'
|
||
echo $myresult
|
||
}
|
||
```
|
||
|
||
```bash
|
||
result="$(myfunc)"
|
||
```
|
||
|
||
### 抛出错误
|
||
|
||
```bash
|
||
myfunc() {
|
||
return 1
|
||
}
|
||
```
|
||
|
||
```bash
|
||
if myfunc; then
|
||
echo "success"
|
||
else
|
||
echo "failure"
|
||
fi
|
||
```
|
||
|
||
Bash 选项
|
||
-------
|
||
<!--rehype:body-class=cols-2-->
|
||
|
||
### 选项
|
||
|
||
避免覆盖文件
|
||
|
||
```bash
|
||
# (echo "hi" > foo)
|
||
set -o noclobber
|
||
```
|
||
|
||
用于出错时退出，避免级联错误
|
||
|
||
```bash
|
||
set -o errexit
|
||
```
|
||
|
||
揭示隐藏的失败
|
||
|
||
```bash
|
||
set -o pipefail
|
||
```
|
||
|
||
公开未设置的变量
|
||
|
||
```bash
|
||
set -o nounset
|
||
```
|
||
|
||
### 全局选项
|
||
|
||
不匹配的 glob 被删除
|
||
|
||
```bash
|
||
shopt -s nullglob # ('*.foo' => '')
|
||
```
|
||
|
||
不匹配的 glob 抛出错误
|
||
|
||
```bash
|
||
shopt -s failglob
|
||
```
|
||
|
||
不区分大小写的球体
|
||
|
||
```bash
|
||
shopt -s nocaseglob
|
||
```
|
||
|
||
通配符匹配点文件
|
||
|
||
```bash
|
||
shopt -s dotglob # ("*.sh" => ".foo.sh")
|
||
```
|
||
|
||
允许 ** 进行递归匹配
|
||
|
||
```bash
|
||
shopt -s globstar # ('lib/**/*.rb' => 'lib/a/b/c.rb')
|
||
```
|
||
|
||
Bash 历史
|
||
-------
|
||
<!--rehype:body-class=cols-2-->
|
||
|
||
### 命令
|
||
|
||
命令 | 描述
|
||
:- | -
|
||
`history` | 显示历史
|
||
`sudo !!` | 使用 `sudo` 运行上一个命令
|
||
`shopt -s histverify` | 不要立即执行扩展结果
|
||
<!--rehype:className=left-align-->
|
||
|
||
### 表达式
|
||
|
||
表达式 | 描述
|
||
:- | -
|
||
`!$` | 展开最新命令的最后一个参数
|
||
`!*` | 展开最新命令的所有参数
|
||
`!-n` | 展开第 `n` 个最近的命令
|
||
`!n` | 展开历史中的第 `n` 个命令
|
||
`!<command>` | 展开最近调用的命令 `<command>`
|
||
<!--rehype:className=left-align-->
|
||
|
||
### 操作
|
||
|
||
代码 | 描述
|
||
:- | -
|
||
`!!` | 再次执行最后一条命令
|
||
`!!:s/<FROM>/<TO>/` | 在最近的命令中将第一次出现的 `<FROM>` 替换为 `<TO>`
|
||
`!!:gs/<FROM>/<TO>/` | 在最近的命令中将所有出现的 `<FROM>` 替换为 `<TO>`
|
||
`!$:t` | 仅从最近命令的最后一个参数扩展基本名称
|
||
`!$:h` | 仅从最近命令的最后一个参数展开目录
|
||
<!--rehype:className=left-align-->
|
||
|
||
`!!` 和 `!$` 可以替换为任何有效的扩展。
|
||
|
||
### 切片 Slices
|
||
|
||
代码 | 描述
|
||
:- | -
|
||
`!!:n` | 仅扩展最近命令中的第 `n` 个标记(命令为 `0`；第一个参数为 `1`)
|
||
`!^` | 从最近的命令展开第一个参数
|
||
`!$` | 从最近的命令中展开最后一个标记
|
||
`!!:n-m` | 从最近的命令扩展令牌范围
|
||
`!!:n-$` | 从最近的命令中将第 `n` 个标记展开到最后
|
||
<!--rehype:className=left-align-->
|
||
|
||
`!!` 可以替换为任何有效的扩展，即 `!cat`、`!-2`、`!42` 等。
|
||
|
||
杂项
|
||
---
|
||
|
||
### 数值计算
|
||
|
||
```bash
|
||
$((a + 200)) # $a 加 200
|
||
```
|
||
|
||
```bash
|
||
$(($RANDOM%200)) # 随机数 0..199
|
||
```
|
||
|
||
### 子 shell
|
||
|
||
```bash
|
||
(cd somedir; echo "I'm now in $PWD")
|
||
pwd # 仍然在第一个目录
|
||
```
|
||
|
||
### 检查命令
|
||
|
||
```bash
|
||
command -V cd
|
||
#=> "cd 是一个函数/别名/其他"
|
||
```
|
||
|
||
### 重定向
|
||
<!--rehype:wrap-class=row-span-2 col-span-2-->
|
||
|
||
```bash
|
||
python hello.py > output.txt # 标准输出到(文件)
|
||
python hello.py >> output.txt # 标准输出到(文件)，追加
|
||
python hello.py 2> error.log # 标准错误到(文件)
|
||
python hello.py 2>&1 # 标准错误到标准输出
|
||
python hello.py 2>/dev/null # 标准错误到(空null)
|
||
python hello.py &>/dev/null # 标准输出和标准错误到(空null)
|
||
```
|
||
|
||
```bash
|
||
python hello.py < foo.txt # 将 foo.txt 提供给 python 的标准输入
|
||
```
|
||
|
||
### 来源相对
|
||
|
||
```bash
|
||
source "${0%/*}/../share/foo.sh"
|
||
```
|
||
|
||
### 脚本目录
|
||
|
||
```bash
|
||
DIR="${0%/*}"
|
||
```
|
||
|
||
### Case/switch
|
||
|
||
```bash
|
||
case "$1" in
|
||
start | up)
|
||
vagrant up
|
||
;;
|
||
*)
|
||
echo "Usage: $0 {start|stop|ssh}"
|
||
;;
|
||
esac
|
||
```
|
||
|
||
### 陷阱错误
|
||
<!--rehype:wrap-class=col-span-2-->
|
||
|
||
```bash
|
||
trap 'echo Error at about $LINENO' ERR
|
||
```
|
||
|
||
或者
|
||
|
||
```bash
|
||
traperr() {
|
||
echo "ERROR: ${BASH_SOURCE[1]} at about ${BASH_LINENO[0]}"
|
||
}
|
||
set -o errtrace
|
||
trap traperr ERR
|
||
```
|
||
|
||
### printf
|
||
|
||
```bash
|
||
printf "Hello %s, I'm %s" Sven Olga
|
||
#=> "Hello Sven, I'm Olga
|
||
|
||
printf "1 + 1 = %d" 2
|
||
#=> "1 + 1 = 2"
|
||
|
||
printf "Print a float: %f" 2
|
||
#=> "Print a float: 2.000000"
|
||
```
|
||
|
||
### 获取选项
|
||
<!--rehype:wrap-class=col-span-2-->
|
||
|
||
```bash
|
||
while [[ "$1" =~ ^- && ! "$1" == "--" ]]; do case $1 in
|
||
-V | --version )
|
||
echo $version
|
||
exit
|
||
;;
|
||
-s | --string )
|
||
shift; string=$1
|
||
;;
|
||
-f | --flag )
|
||
flag=1
|
||
;;
|
||
esac; shift; done
|
||
if [[ "$1" == '--' ]]; then shift; fi
|
||
```
|
||
|
||
### 检查命令的结果
|
||
|
||
```bash
|
||
if ping -c 1 google.com; then
|
||
echo "看来您的互联网连接正常"
|
||
fi
|
||
```
|
||
|
||
### grep 检查
|
||
|
||
```bash
|
||
if grep -q 'foo' ~/.bash_history; then
|
||
echo "您过去似乎输入过“foo”"
|
||
fi
|
||
```
|
||
|
||
### 写入文件
|
||
<!--rehype:wrap-class=row-span-6-->
|
||
|
||
:-- | --
|
||
:-- | --
|
||
`cat` | 用于显示文本文件内容，全部输出
|
||
`EOF` | `end of file`，表示文本结束符
|
||
|
||
---
|
||
|
||
```bash
|
||
cat > output.txt <<EOF
|
||
this is test eof
|
||
this is test eof2
|
||
EOF
|
||
```
|
||
|
||
输出 `cat output.txt`
|
||
|
||
```
|
||
this is test eof
|
||
this is test eof2
|
||
```
|
||
|
||
追加内容
|
||
|
||
```bash
|
||
cat >>2.txt <<EOF
|
||
456
|
||
789
|
||
EOF
|
||
```
|
||
|
||
`$` 等特殊字符时，须利用转义字符 `\`
|
||
|
||
```bash
|
||
cat > file <<EOF
|
||
export ORACLE_SID=yqpt
|
||
export PATH=\$PATH:\$ORACLE_HOME/bin
|
||
EOF
|
||
```
|
||
|
||
取消变量替换，`EOF` 被加上双引号或者单引号，即可取消变量的替换
|
||
|
||
```bash
|
||
cat << "EOF" > output.sh
|
||
echo "This is output"
|
||
echo $1
|
||
EOF
|
||
```
|
||
|
||
所有TAB键将全部忽略[不能是空格]
|
||
|
||
```bash
|
||
cat << -EOF
|
||
echo "This is output"
|
||
EOF
|
||
```
|
||
|
||
### 特殊变量
|
||
<!--rehype:wrap-class=row-span-2-->
|
||
|
||
表达式 | 描述
|
||
:- | -
|
||
`$?` | 最后一个任务的退出状态
|
||
`$!` | 最后一个后台任务的 PID
|
||
`$$` | shell PID
|
||
`$0` | shell 脚本的文件名
|
||
|
||
见[特殊参数](http://wiki.bash-hackers.org/syntax/shellvars#special_parameters_and_shell_variables)。
|
||
|
||
### 反斜杠转义
|
||
<!--rehype:wrap-class=row-span-2-->
|
||
|
||
-
|
||
- \!
|
||
- \"
|
||
- \#
|
||
- \&
|
||
- \'
|
||
- \(
|
||
- \)
|
||
- \,
|
||
- \;
|
||
- \<
|
||
- \>
|
||
- \[
|
||
- \|
|
||
- \\
|
||
- \]
|
||
- \^
|
||
- \{
|
||
- \}
|
||
- \`
|
||
- \$
|
||
- \*
|
||
- \?
|
||
<!--rehype:className=cols-4 style-none-->
|
||
|
||
使用 `\` 转义这些特殊字符
|
||
|
||
### Heredoc
|
||
|
||
```sh
|
||
cat <<END
|
||
hello world
|
||
END
|
||
```
|
||
|
||
### 转到上一个目录
|
||
|
||
```bash
|
||
pwd # /home/user/foo
|
||
cd bar/
|
||
pwd # /home/user/foo/bar
|
||
cd -
|
||
pwd # /home/user/foo
|
||
```
|
||
|
||
### 读取输入
|
||
|
||
```bash
|
||
echo -n "Proceed? [y/n]: "
|
||
read ans
|
||
echo $ans
|
||
```
|
||
|
||
```bash
|
||
read -n 1 ans # 只有一个字符
|
||
```
|
||
|
||
### 条件执行
|
||
|
||
```bash
|
||
git commit && git push
|
||
git commit || echo "Commit failed"
|
||
```
|
||
|
||
### 严格模式
|
||
|
||
```bash
|
||
set -euo pipefail
|
||
IFS=$'\n\t'
|
||
```
|
||
|
||
参见：[非官方 bash 严格模式](http://redsymbol.net/articles/unofficial-bash-strict-mode/)
|
||
|
||
### 可选参数
|
||
|
||
```bash
|
||
args=("$@")
|
||
args+=(foo)
|
||
args+=(bar)
|
||
echo "${args[@]}"
|
||
```
|
||
|
||
将参数放入数组中，然后追加
|
||
|
||
### 调试模式
|
||
|
||
启用调试模式，会把脚本中的每条命令的执行情况打印出来。它可以在整个会话或脚本上运行，也可以在脚本内以编程方式启用。
|
||
|
||
以调试模式运行脚本(整个脚本都会打印调试信息)：
|
||
|
||
```bash
|
||
$ bash -x myscript.sh
|
||
```
|
||
|
||
在 bash 脚本中打开调试(针对部分内容打印调试信息)
|
||
|
||
```bash
|
||
#!/bin/bash
|
||
set -x # Enable debugging
|
||
# some code here
|
||
set +x # Disable debugging output.
|
||
```
|
||
|
||
Bash 颜色
|
||
----
|
||
|
||
### 颜色着色语法示例
|
||
<!--rehype:wrap-class=row-span-2-->
|
||
|
||
您可以通过为其输出着色来使您的 BASH 脚本更漂亮，使用以下模板编写彩色文本：
|
||
|
||
#### 示例
|
||
|
||
```bash
|
||
$ echo -e "\e[31m命令行中显示红色文字\e[0m"
|
||
```
|
||
|
||
<red>命令行中显示红色文字</red>
|
||
|
||
```
|
||
$ echo -e "\e[42m绿色背景\e[0m"
|
||
```
|
||
|
||
`绿色背景`<!--rehype:style=background:green;color: black;-->
|
||
|
||
Option | Description
|
||
:- | --
|
||
`-e` | 启用反斜杠转义的解释
|
||
`\e[` 或 `\x1b[` 或 `\033[` | 开始颜色修改
|
||
`COLORm` | 颜色代码 + `m` 在末尾
|
||
`\e[0m` 或 `\x1b[0m` 或 `\033[0m` | 结束颜色修改
|
||
<!--rehype:className=left-align-->
|
||
|
||
`0x1b` 字面上称为 `ESC`
|
||
|
||
#### 示例
|
||
|
||
```bash
|
||
$ echo -e "\e[3m下划线文本\e[0m"
|
||
```
|
||
|
||
`下划线文本`<!--rehype:style=text-decoration: underline;color: inherit;-->
|
||
|
||
```bash
|
||
$ echo -e "\e[1;33;4;44m粗体下划线蓝色背景黄色文字的文本\e[0m"
|
||
```
|
||
<!--rehype:className=wrap-text-->
|
||
|
||
`粗体下划线蓝色背景黄色文字的文本`<!--rehype:style=text-decoration: underline;color: inherit;font-weight: bold;color: #cdcd00;background: #0000ee;-->
|
||
|
||
```bash
|
||
\e[ # 启用转义
|
||
1;33;4;44 # 参数 (1;33;4;44)
|
||
m # 设置图形模式
|
||
```
|
||
|
||
#### 样式
|
||
|
||
:- | -- | --
|
||
:- | -- | --
|
||
`0` | 普通字符(复位或正常) | 关闭所有属性
|
||
`1` | **粗体**字
|
||
`2` | 弱化(降低强度) | 未广泛支持
|
||
`3` | 斜体 | 未广泛支持有时为反相显示
|
||
`4` | 下划线
|
||
`5` | 缓慢闪烁
|
||
`6` | 快速闪烁
|
||
`7` | 反显
|
||
`8` | 隐藏 | 未广泛支持
|
||
`9` | 划除
|
||
<!--rehype:className=left-align-->
|
||
|
||
### ANSI — 颜色转义码
|
||
|
||
颜色 | 名称 | 前景色 | 背景色 | 示例
|
||
:- | --| -- | -- | --
|
||
`Black` | 黑色 | 30 | 40 | `黑`<!--rehype:style=background:#000;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Red` | 红色 | 31 | 41 | `红`<!--rehype:style=background:#c23621;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Green` | 绿色 | 32 | 42 | `绿`<!--rehype:style=background:#25bc26;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Yellow` | 黄色 | 33 | 43 | `黄`<!--rehype:style=background:#cdcd00;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Blue` | 蓝色 | 34 | 44 | `蓝`<!--rehype:style=background:#0000ee;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Purple` | 紫色 | 35 | 45 | `紫`<!--rehype:style=background:#cd00cd;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Cyan` | 青色 | 36 | 46 | `青`<!--rehype:style=background:#00AAAA;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`White` | 白色 | 37 | 47 | `白`<!--rehype:style=background:#e5e5e5;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
<!--rehype:className=show-header left-align-->
|
||
|
||
### ANSI — 颜色转义码(亮色)
|
||
|
||
颜色 | 前色 | 背色 | 示例
|
||
:- | -- | -- | --
|
||
`BrightBlack(Gray)` 灰色 | 90 | 100 | `90`<!--rehype:style=background:#555555;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright Red` 亮红色 | 91 | 101 | `91`<!--rehype:style=background:#FF5555;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright Green` 亮绿色 | 92 | 102 | `92`<!--rehype:style=background:#55FF55;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright Yellow` 亮黄色 | 93 | 103 | `93`<!--rehype:style=background:#FFFF55;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright Blue` 亮蓝色 | 94 | 104 | `94`<!--rehype:style=background:#5555FF;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright Magenta` 亮紫色 | 95 | 105 | `95`<!--rehype:style=background:#FF55FF;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright Cyan` 亮青色 | 96 | 106 | `96`<!--rehype:style=background:#55FFFF;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
`Bright White` 浅灰 | 97 | 107 | `97`<!--rehype:style=background:#ffffff;padding:0.2rem 1.2rem;border: 1px solid #333;-->
|
||
<!--rehype:className=show-header left-align-->
|
||
|
||
### 可用功能
|
||
<!--rehype:wrap-class=col-span-2-->
|
||
|
||
:- | -- | --
|
||
:- | -- | --
|
||
`n` A | 光标上移 | 光标向指定的方向移动 `n`(默认1)格
|
||
`n` B | 光标下移 | 光标向指定的方向移动 `n`(默认1)格
|
||
`n` C | 光标前移 | 光标向指定的方向移动 `n`(默认1)格
|
||
`n` D | 光标后移 | 光标向指定的方向移动 `n`(默认1)格
|
||
`n` E | 光标移到下一行 | 光标移动到下面第 `n`(默认1)行的开头(非ANSI.SYS)
|
||
`n` F | 光标移到上一行 | 光标移动到上面第 `n`(默认1)行的开头(非ANSI.SYS)
|
||
`n` G | 光标水平绝对 | 光标移动到第 `n`(默认1)列(非ANSI.SYS)
|
||
`n`;`m` H | 光标位置 | 光标移动到第 `n`行、第 `m` 列。值从1开始，且默认为1(左上角)
|
||
`n` J | ED – 擦除显示 | 清除屏幕的部分区域
|
||
`n` K | EL – 擦除行 | 清除行内的部分区域
|
||
`n` S | SU – 向上滚动 | 整页向上滚动 `n`(默认1)行。新行添加到底部 (非ANSI.SYS)
|
||
`n` T | SD – 向下滚动 | 整页向下滚动 `n`(默认1)行。新行添加到顶部 (非ANSI.SYS)
|
||
`n`;`m`f | HVP – 水平垂直位置 | 同CUP
|
||
`n` `m` | SGR – 选择图形再现 | 设置SGR参数，包括文字颜色
|
||
`5i` | 打开辅助端口 | 启用辅助串行端口，通常用于本地串行打印机
|
||
`4i` | 关闭辅助端口 | 禁用辅助串行端口，通常用于本地串行打印机
|
||
`6n` | DSR – 设备状态报告 | 以 `ESC[n;mR` (就像在键盘上输入)向应用程序报告光标位置(CPR)，其中 `n`是行， `m` 是列
|
||
`s` | SCP – 保存光标位置 | 保存光标的当前位置
|
||
`u` | RCP – 恢复光标位置 | 恢复保存的光标位置
|
||
<!--rehype:className=left-align-->
|
||
|
||
另见
|
||
----
|
||
|
||
- [Shell 教程](https://jaywcjlove.github.io/shell-tutorial) _(jaywcjlove.github.io)_
|
||
- [Devhints](https://devhints.io/bash) _(devhints.io)_
|
||
- [Bash-hackers wiki](http://wiki.bash-hackers.org/) _(bash-hackers.org)_
|
||
- [Shell vars](http://wiki.bash-hackers.org/syntax/shellvars) _(bash-hackers.org)_
|
||
- [Learn bash in y minutes](https://learnxinyminutes.com/docs/bash/) _(learnxinyminutes.com)_
|
||
- [Bash Guide](http://mywiki.wooledge.org/BashGuide) _(mywiki.wooledge.org)_
|
||
- [ShellCheck](https://www.shellcheck.net/) _(shellcheck.net)_
|
||
- [shell - Standard Shell](https://devmanual.gentoo.org/tools-reference/bash/index.html) _(devmanual.gentoo.org)_
|
||
- [ANSI 转义序列](https://zh.wikipedia.org/wiki/ANSI转义序列) _(zh.wikipedia.org)_
|