hot key
Ctrl + c Terminate the program running in the foreground
Ctrl + z Suspend the program running in the foreground to the background
Ctrl + d Exit equivalent exit
Ctrl + l Clear the screen
Ctrl + a |home Move the cursor to the front of the command line
Ctrl + e |end Move the cursor to the back end of the command line
Ctrl + u Delete all characters before the cursor
Ctrl + k Delete all characters after the cursor
Ctrl + r Search history commands
wildcard
symbol |
effect |
* |
matches 0 or more of any character |
? |
matches any single character |
! |
reconciliation |
[list] |
Match any single character in [list], or a set of single characters [az] |
[!list] |
Matches any single character except in list |
{string1,string2,...} |
Match string1, string2 or more strings |
special symbols
symbol |
effect |
double quotes "" |
will treat the content of the quotation marks as a whole, Allows referencing other variable values via the $ sign . |
single quote '' |
The content of the quotation marks will be treated as a whole, and it is forbidden to quote other variable values . Special symbols in the shell are treated as ordinary characters. |
Backtick `` |
Backticks are the same as $() , commands in quotes or brackets will be executed first , If there is nesting, backticks cannot be used. |
Shell Scripts
interpreter
If you directly write the interpreter path in the script,
there may be a compatibility ,
so you can use: #!/bin/env interpreter ==> #!/bin/ env bash
bash parameter
-x : Generally used for troubleshooting, check the execution process of the script bash -x [shell script]
-n : Used to check if there is a problem with the syntax of the script bash -n [shell script]
script contents
# specify the interpreter
Description of the basic information of the script
Script details
#!/bin/env bash
# 基本信息描述
# Name: t17.sh
# Desc: rm tmp/* + create dir1~dir3
# Path: ./
# Usage:
# Update: 20230109
pwd
ls -l /tmp1/
echo "===delete /tmp1/files==="
rm -rf /tmp1/*
ls -l /tmp1/
echo " files have been delete , /tmp1 no dir"
echo "===create /tmp1/files==="
mkdir -p /tmp1/dir{1..3}
ls -l /tmp1/
echo "/tmp1 has 3 dir"
echo "===cp sh scripts to /tmp1/files==="
cp -rf ./*.sh /tmp1/dir1
ls -l /tmp1/dir1
echo "cp finsh"
echo "scripts run success, $(date +'%F %T') finish" # "+" 后面必须紧密连接'%F ,不能有空格
date
Linux date command | Rookie Tutorial (runoob.com)
%% 输出字符 %
%a 星期几的缩写 (Sun..Sat)
%A 星期的完整名称(Sunday..Saturday)。
%b 缩写的月份名称(例如,Jan)
%B 完整的月份名称(例如,January)
%c 本地日期和时间(例如,Thu Mar 3 23:05:25 2005)
%C 世纪,和%Y类似,但是省略后两位(例如,20)
%d 日 (01..31)
%D 日期,等价于%m/%d/%y
%e 一月中的一天,格式使用空格填充,等价于%_d
%F 完整的日期;等价于 %Y-%m-%d
%g ISO 标准计数周的年份的最后两位数字
%G ISO 标准计数周的年份,通常只对%V有用
%h 等价于 %b
%H 小时 (00..23)
%I 小时 (01..12)
%j 一年中的第几天 (001..366)
%k 小时,使用空格填充 ( 0..23); 等价于 %_H
%l 小时, 使用空格填充 ( 1..12); 等价于 %_I
%m 月份 (01..12)
%M 分钟 (00..59)
%n 新的一行,换行符
%N 纳秒 (000000000..999999999)
%p 用于表示当地的AM或PM,如果未知则为空白
%P 类似 %p, 但是是小写的
%r 本地的 12 小时制时间(例如 11:11:04 PM)
%R 24 小时制 的小时与分钟; 等价于 %H:%M
%s 自 1970-01-01 00:00:00 UTC 到现在的秒数
%S 秒 (00..60)
%t 插入水平制表符 tab
%T 时间; 等价于 %H:%M:%S
%u 一周中的一天 (1..7); 1 表示星期一
%U 一年中的第几周,周日作为一周的起始 (00..53)
%V ISO 标准计数周,该方法将周一作为一周的起始 (01..53)
%w 一周中的一天(0..6),0代表星期天
%W 一年中的第几周,周一作为一周的起始(00..53)
%x 本地的日期格式(例如,12/31/99)
%X 本地的日期格式(例如,23:13:48)
%y 年份后两位数字 (00..99)
%Y 年
%z +hhmm 格式的数值化时区格式(例如,-0400)
%:z +hh:mm 格式的数值化时区格式(例如,-04:00)
%::z +hh:mm:ss格式的数值化时区格式(例如,-04:00:00)
%:::z 数值化时区格式,相比上一个格式增加':'以显示必要的精度(例如,-04,+05:30)
%Z 时区缩写 (如 EDT)