Programmer Think

First of all, I wrote this code a long time ago, and then there were many places I didn't understand at that time. Now let's take a look at this code. I really feel ugly and want to change it, but it's really hard to change it Therefore, writing code and specification are really important. Functions realized: User private chatGroup chat ...

Reference: Qt Creator quick start, Third Edition, edited by Huo Yafei 1,UDP UDP(User Datagram Protocol) is a lightweight, unreliable, datagram oriented and connectionless protocol, which is used when reliability is not very important. UDP is generally divided into sender and receiver. QUdpSocket class is used to send and receive UDP datagram ...

summary The data flowing through the network always has the same type: bytes. How these bytes are transmitted mainly depends on what we call network transmission. Users do not care about the details of transmission, only whether bytes are reliably sent and received If you use Java network programming, you will find that sometimes when you n ...

1. Three elements of network programming Network programming refers to the program running on different computers under the network communication protocol, which can carry out data transmission 1.1 IP address IP address: it is the unique identification of the device in the network IP addresses fall into two categories: IPv4: assign a 32bit ...

Reference article: Porting libpcap packet capture library to arm platform under LinuxLinux Network Programming -- detailed explanation of libpcaplibpcap usageLibpcap library programming guide – packet captureMethods of network monitoring and sending data packets under linux (i.e. the use of libpcap and libnet class libraries) 1, lib ...

WebSocket notes Websocket: HTML5 WebSocket is designed to replace polling and long connection, so that the client browser has the instant messaging capability of desktop system under C/S framework, and realizes full duplex communication between browser and server. It is based on TCP. Although websocket transmits data through TCP like HTTP, ...

Introduction to python crawler (1) Getting started with Requests Library I Requests Library 1. Installation Enter pip install requests on the cmd command line 🆗 Yes Test code #Climb Baidu home page import requests r= requests.get("http://www.baidu.com") print(r.status_code) r.encoding='utf-8' print(r.text) Operation results: ...

Socket.IO notes Instant messaging is based on TCP long connection. After the connection is established, the client / server can send data to the opposite end at any time for unlimited times, so as to realize the immediacy of server data transmission HTTP HTTP is a short link, which is designed to reduce the pressure on the server ...

Introduction to network communication According to the number of recipients, network data transmission can be divided into the following three ways. ·Unicast: provides point-to-point communication. The data sent by the sender each time has a unique destination address and is received by only one receiver. ·Broadcast: the data ...

1. Non blocking IO and blocking IO (1) Difference between non blocking IO and blocking IO: Non blocking IO is that the user directly obtains a result without waiting after sending an IO request. It is usually used with O_NONBLOCK works with fcntl. Blocking IO is that when the user thread sends an IO request, the kernel will check whether the ...