IO multiplexing -- select system call

IO multiplexing The client program processes multiple socket s. (e.g. non blocking connect) The client program processes both user input and network connections. (e.g. chat program) The server should handle listening socket and connecting socket at the same time. The server processes both TCP and UDP ...

Posted by RHolm on Thu, 16 Jan 2020 03:20:56 -0800

Java design pattern type adapter pattern

Article directory 1: Adapter mode 1.1 adapter mode 1.1.1 precautions and details of type 1 adapter mode 1.2 object adapter mode 1.2.1 precautions and details of object adapter mode 1.3 interface adapter mode (default adapter mode) 2: Adapter mode considerations and details 1: Adapter mode Basi ...

Posted by the mysox1 on Wed, 15 Jan 2020 01:02:50 -0800

Integration of vue project with ID reader (hi-fi) in front end

Recently, when working on background management projects, I encountered a problem that I used the high-resolution meter to read the identity card information (Nada high-resolution meter) and then integrated it on the page. At that time, I was confused about how to integrate the hardware interaction i ...

Posted by jaybird84404 on Tue, 14 Jan 2020 23:41:56 -0800

GPDB feature practice

date: 2020-01-11 15:51:39 Some time ago, my tutor asked me to know about the GreenPlum database. Later, I installed and used it for a while. It felt like it was no different from other databases, so it ended up. Now go over the features of GPDB and try to use them. In fact, I really need to understand t ...

Posted by vinoth on Tue, 14 Jan 2020 19:06:09 -0800

Building a remote monitoring system using nodejs and python 1. Video capture module

How to use python and nodejs to build a remote monitoring system without saying anything. 1. Platform and Environment Python 3.6, opencv3.0 or above (or some functionality in cv2 is unavailable) nodejs8.9.4 relies on the following { "name": "video", "version": "1.0.0", "description": "Simple live video program", "m ...

Posted by mgmoses on Mon, 13 Jan 2020 08:07:10 -0800

windows socket programming demo

WINDOWS SOCKET programming example Important points: Server side Client Code See? You don't need to know the ip and port of the client in the whole process of socket programming at the code level. The following protocol stack will detect it by itself. But socket is actually to use the client's ip a ...

Posted by GreyFilm on Sat, 11 Jan 2020 07:02:12 -0800

Summary of MySQL 8 Anti-Join

Guidance: Author: Zheng Songhua, Zhi Shu Tang's SQL Optimized Class Teacher, Net Name: Rabbit Riding Tortoise Today, I would like to share some articles about not in, not exists.In fact, this can be summarized as exists to in, which was treated differently in previous versions of mysql until version 8.0.16. Prior to version 16, in could be op ...

Posted by eyespark on Tue, 07 Jan 2020 18:55:46 -0800

Redis Pipeline Pipeline Use

1.Redis single command usage scenario The following steps are required for a Redis client to connect to a Redis server to execute a command: The above process is called Round Trip Time (RTT), and the mget and mset commands save RTT, but most commands do not support batch operations. Redis provides services through TCP, Client initiates r ...

Posted by holowugz on Tue, 07 Jan 2020 00:57:11 -0800

Remember the blood case caused by a pass file handle (continued)

Following Remember a blood case caused by passing a file handle once After that, the demo triggered another blood case, which is now recorded below. This time I'm testing file handle transfer on linux, which does not have a STREAMS system. The handle is therefore passed using the control message part in sendmsg/recvmsg of the unix domain socke ...

Posted by srikanth03565 on Mon, 06 Jan 2020 08:52:54 -0800

PHP Socket server building and testing

1.socket server building ideas 1) Objective: to understand the working mechanism of socket server 2) Idea: create socket - > Add socket to connection pool - > process receiving information - > handshake action - > send information   2.socket server code Note: copy to php file, direct command line can run, no other support is requi ...

Posted by jdiver on Fri, 03 Jan 2020 23:13:03 -0800