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Nameless pipe ❤️ ❤️ ❤️ Pipe is also called anonymous pipe. It is the oldest form of IPC (interprocess communication) in UNIX system. All UNIX systems support this communication mechanism.When the parent process calls the pipe function, the kernel will create a cache in the kernel space when executing the pipe function. This cache is the ...

openssl certificate 1, Introduction to openssl openssl is the most popular SSL cryptographic library tool at present. It provides a general, robust and fully functional tool suite to support the implementation of SSL/TLS protocol. Official website: https://www.openssl.org/source/ Component Cryptographic algorithm library Key and certificate en ...

1 Overview In the last article [Package] RosBridge -- break through the data barrier between Ros and non Ros environment In this article, I introduced how to conduct data communication between non Ros and Ros systems through RosBridge, and realized half of the communication architecture, that is, the left half of the picture. In this article, ...

1, Error reporting page 2, Error reporting reason This error occurs in MySQL version 5.7 and above: The default sql configuration for MySQL version 5.7 is sql_mode = "ONLY_FULL_GROUP_BY", this configuration strictly implements the "SQL92 standard". When upgrading from 5.6 to 5.7, most of them choose to adjust SQL for syn ...

1: Nginx installation configuration 1. Install compilation tools and library files yum -y install make zlib zlib-devel gcc-c++ libtool openssl openssl-devel 2. First install PCRE PCRE is used to enable Nginx to support Rewrite. Download the PCRE installation package at: http://downloads.sourceforge.net/project/pcre/pcre/8.35/pcre-8.35.tar.gz E ...

Basic concepts of digital certificateStandards for digital certificates10. 509 version number: indicates which version of X.509 standard is used in the certificate. The version number will affect some specific information in the certificateSerial number: a unique digital number assigned to each certificate by the CA. when the certificate is can ...

Reference link: Alibaba open source mirror station NTP download installation tutorial 1, NTP server introduction Network Time Protocol Network time protocol (NTP) server, also known as NTP server, is used to provide time synchronization services. In the production environment, many people ignore the time problem. In fact, the time synchronizat ...

catalogue 1. touch command 2. mkdir command 3. cp command 4. mv command 5. rm command 6. dd command 7. file command 1. touch command touch The command is used to create a blank file or set the time of the file in the format“ touch [ option ] [ file ] ". In creating a blank text file, this touch The command ...

Linux awk command details 1, awk working principle Read the text line by line. By default, the text is separated by a space or tab key. Save the separated fields to the built-in variable, and execute the editing command according to the mode or condition. The sed command is often used to process a whole line, while awk prefers to divide a l ...

GitHub Linux source code Reference link 1 Reference link 2 Reference link III Reference link 4 Multiplexing technology: process multiple times on a single channel and process multiple events with a single thread.The IO mentioned here mainly refers to the network io. In Linux, everything is a file, so the network IO is often represented by the ...