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preface We will show you a go zero micro service example in detail through a series of articles. The whole series is divided into ten articles, and the directory structure is as follows: Environment construction Service splitting User services Product service Order service Payment services RPC service Auth authentication Serv ...

shell_01 File expression if [ -f file ] If the file exists if [ -d ... ] If directory exists if [ -s file ] If the file exists and is not empty if [ -r file ] If the file exists and is readable if [ -w file ] If the file exists and is writable if [ -x file ] If the file exists and is executable Integer variable expression if [ int1 -eq int ...

7. Conditional judgment Conditional judgment syntax format Format 1: test Conditional expression Format 2:[ Conditional expression ] #Pay attention to the spaces Format 3:[[Conditional expression]] #regular expression Relevant parameters of condition judgment Q: what do you want to judge? A: I want to judge the file type, wheth ...

This article is reproduced from Ruan Yifeng's Weblog awk tutorial 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. aw ...

Docker and operating systemLinux distributionCommon are Ubuntu, Alpine, CentOS, Debian, etc. You can download the Linux distribution image with the following command:docker pull ubuntu docker pull alpine docker pull centos docker pull debianUsing docker images, you can view the image information and compare the image sizes of different distribu ...

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 ...

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 ...

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 ...

preface We will show you a go zero micro service example in detail through a series of articles. The whole series is divided into ten articles, and the directory structure is as follows: Environment construction Service splitting User services (this article) Product service Order service Payment services RPC service Auth authen ...

reference material Video link Operating environment windows10Linux CentOS 7Xshell 7 1, Process control 1.1 if judgment Basic grammar #Writing method I if [ Conditional judgment ]; then program fi #Writing method 2 if [ Conditional judgment] then program fi Precautions: (1) [conditional judgment], there must be a space ...