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Catalog   1. SED of Three Swordsmen 1.1. Fundamentals 1.1.1. Summary 1.1.2. grammar 1.2. List display 1.2.1. Add in/etc/passwd line 4 1.2.2. Append insert 1.2.3. delete 1.2.4. replace 1.2.5. Print Display 1.2.6. Multipoint Editing 1.2.7 Modify text content 2. AWK of Three Swordsmen 2.1. Summary 2.2. grammar 2.3. List 2.3.1. Se ...

-----Latest update [December 30, 2021]----- Preview of this article's directory structure: 1, Introduction 2, shell variable 1. View variables 2. Variable type 3. Variable operation 4. Common global variables in the system 3, shell options 1. View shell options 2. Set shell options 4, Metacharacter 1. Metacharacter list 2. Citation and escape ...

Writing script rules 1. Declaration interpreter #!/bin/bash bash benefits: history, tab, pipeline, redirection, alias 2. Notes 3. Code 1. Write a script to create a user, enter the user name and password, enter the user name as empty, and exit the script #! /bin/bash read -p 'Please enter the user name you want to create' a [ -z $a ] &amp ...

Click Redis installation Make the file have miscellaneous attributes chmod a+x /etc/init.d/redis Crond service related commands( reference resources) crond service To install crontab: yum install crontabs Service operation instructions: /sbin/service crond start //Start service /sbin/service crond stop //Shut down service /sbin/se ...

Preliminary preparation (Linux system is installed by default) Demo system: Ubuntu standalone system Linux The-Land-Like-as-A-Picture 5.8.0-59-generic #66~20.04.1-Ubuntu SMP Thu Jun 17 11:14:10 UTC 2021 x86_64 x86_64 x86_64 GNU/LinuxVirtual machine Vmware 15 CentOS 7 1. Network configuration: Independent system Configuration is complet ...

1. Overview 1. Concepts 1) What is a shell: shell Is a command interpreter, which is responsible for directly talking with the user at the outermost level of the operating system, interpreting the user's input to the operating system, processing the output of a wide variety of operating systems, and outputting to the screen for feedback ...

What are variables? Variable is an indispensable part of any language, which is used to store all kinds of data. Scripting languages usually do not need to declare types before using variables, but only need to assign values directly. Environment variables: some special variables will be used by shell script or operating system environment to ...

I Shell background 1.1 GNU plan Tips: The GNU Project is a free software, mass collaboration project that Richard Stallman announced on September 27, 1983. Its goal is to give computer users freedom and control in their use of their computers and computing devices by collaboratively developing and publishing software that gives everyon ...

Reference address: Introduction to awk awk is an application for processing text files. Almost all Linux systems come with this program. It processes each line of the file in turn and reads each field in it. awk may be the most convenient tool for text files with the same format per line, such as logs and CSV. 1. Basic usage The basic ...

1, Overview 1. Concept 1) What is a shell: shell It is a command interpreter, which is at the outermost layer of the operating system. It is responsible for directly talking with the user, interpreting the user's input to the operating system, processing various operating system output results, and outputting them to the screen for feedb ...