shell programming

Shell Programming Application: Automated website backup and shell AutomationRsync is a data image backup tool in unix-like systems-remote sync. A Fast Incremental Backup Tool, Remote Sync, supports local replication or synchronization with other SSH and rsync hosts. Compared with traditional cp, scp, and tar backup methods, rsync has the advantages of high securi

Shell The technique of text slicing inIn the shell there is also a string slice this thing exists, has been used in Python slices, the following record the use of slices in the shell.(1) , replacing some of the text in the variable contents$var = "This was a line of text"$ echo${var/line/replaced}This is areplaced of text " Line be replaced by replaced . (2) ,

operating system (many commands support it, and more than 2000 commands are shell-supported)05. Default shell for common operating systemsLinux is Bourne Again shell (bash)Unix:solaris, FreeBSD default is the Bourne shell (SH), AIX is Korn shell (Ksh), HP-UX is the POSIX

variables (1) $? 0 for success, not 0 for failure [ [email protected]~]# Date May 01, 2018 Tuesday 18:58:42 CST [ [email protected]~]# echo $? 0 [ [email protected]~]# RM/ RM: Cannot delete "/": is a directory [ [email protected]~]# echo $? 1 In the enterprise scenario, the use of the $? Return value is as follows: ① to determine whether a program, such as a command, script, or function is successfully executed ② call Exit N in the script, will return this number to $?. ③ in the function, the n

Sub-Library BackupEnterprise Actual Combat Problem 7: How to implement the MySQL database for sub-library backup, please use the script to implement#!/bin/Bashmysqluser=Rootpassword=Rootport=3306Socket="/usr/include/mysql/mysql.sock"Mysqlcmd="mysql-u$mysqluser-p$password-s $Socket"Database= ' $MYSQLCMD-E"show databases;"|egrep-v"Database|_schema|mysql"' MysqlDump="mysqldump-u$mysqluser-p$password-s $Socket"IP= ' Ifconfig enp0s3|grep"Broadcast"|awk'{print $NF}'`//CentOS 7backupdir=/backup/$IP [-D

Case statements are used to implement multiple if. else, but the usage is somewhat different, people who have learned other languages know that the case to match the variables, if there is a matching successful words to execute the corresponding statement. The case statement in Shell programming is also this meaning, cases will match the string, starting from the first mode, if a pattern has been matched su

This blog is simple to look at the loop statements that Shell programming uses, including for loops, while loops, until loops, for behind and a variable, and then a collection that assigns things to this variable, each loop, like a foreach in Java. While loops and if use the same condition to judge, satisfies the condition execution statement, until and while opposite, does not satisfy the condition executi

1. Limitations of single-quote strings: Any character in a single quotation mark is output as is, and the variable in the single-quote string is not valid; Single quotation marks cannot appear in single quote strings (not after using escape characters for single quotes). 2. Advantages of double quotes: You can have variables in double quotes. Escape characters can appear in double quotes 3. Stitching strings:4. Get the string length:5. Extract substrings:6. Look up substrin

1. Understanding Bash Through the shell will input the instructions and kernel communication, let kernel control hardware workView Shell:cat/etc/shellA preset shell type is recorded in the/etc/passwd after login and is related to the accountCommand alias: Alias lm= ' Ls-al ' #注意有无空格Help: Man bashCommand types: Type Copy Code code as follows: Type ls # ls is aliased to ' Ls–color=auto ' Typ

Linux Shell script programming learning notes and practice, Script Programming learning notes Http://www.1987.name/141.html Shell Basics Terminal printing, arithmetic operations, common variables Search for specific strings in a specified directory in Linux and highlight matching keywords Obtain the standard input

menufruit.sh nginx.sh piliangxiugai1.sh piliangxiugai2.sh piliangxiugai3.sh suijiwnjian.sh sum1-100.sh test uptime.sh usage.sh user.sh while1.sh while2.sh while3.sh while4.sh while.sh zhuajiu.sh [[emailprotected] jiaobenlianxi]# cat array03.sh array=( $(ls) ) for((i=0;i 4.Shell Array Knowledge Summary (1) Definition: Static array: array= (1 2 3) space separated Dynamic array: array= ($ (LS)) Assigning a v

Standard input/output (read echo) of shell programming learning notes and shell learning notes 09:32:07 Input read: Purpose: Read a row from the standard input, or read a row from the file descriptor FD (file descriptor) and divide it into fields. Usage:Read [-ers] [-a array] [-d separator] [-I buffer text] [-n read characters] [-N read characters] [-p prompt]

Common commands and statements for Shell programming (SCRIPT) and Common commands for shellSome common Shell programming (SCRIPT) commands and statements can meet general requirements.Command Parameters received: Number of parameters: $ # Parameter value: Command itself: $0 first parameter: $1 second parameter: $2

Linux (7) _ shell script programming, __shell Script Programming I. What is a shell script? In addition to a command interpreter, shell is also a programming language. A program written in she