NIO three components

1. Channel 1.1 what is Channel Channel is similar to Stream. It is a two-way channel for reading and writing data.You can read data from the channel into the buffer or write data from the buffer into the channel. (channel only deals with buffer)The previous stream is either input or output, and channel is lower than stream. 1.2 common channel ...

Posted by jabbaonthedais on Tue, 09 Nov 2021 04:58:10 +0100

UDP broadcast java.net.socketexception under Linux: permission denied

0. Background   first explain the environment: OpenJDK8 CentOS7    secondly, it is common to send messages through UDP broadcasting. When deploying in Linux environment today, the following exceptions occurred when sending messages: java.net.SocketException: insufficient privilege at sun.nio.ch.DatagramChannelImpl.se ...

Posted by wildncrazyath3rt on Thu, 04 Nov 2021 22:23:57 +0100

Socket kernel data structure

In the previous section, we talked about the calling process of Socket in TCP and UDP scenarios. In this section, we will follow this process to the kernel to find out what data structures have been created and what things have been done in the kernel. Parsing socket function Let's start with the Socket system call. SYSCALL_DEFINE3(socket, i ...

Posted by drorgo on Wed, 03 Nov 2021 22:43:41 +0100

Java network programming

Network programming is a program running on different computers under the network communication protocol, which can transmit data   Three elements of network programming IP address         The identification number of the computer, that is, the device identification. The IP address of each computer is different, ...

Posted by Studio381 on Wed, 27 Oct 2021 14:52:22 +0200

Socket and Multithreaded Practice

Review of the previous section: We send data from the application layer to senders and receivers in different buildings. The transport layer has two protocols: TCP / UDP TCP / UDP can be seen as a parallel universe, without interruption. Receiver and sender can use TCP / UDP Each port of the server is isolated from each other. Understand TCP as ...

Posted by furma on Sun, 03 Oct 2021 21:40:38 +0200

DHCP service configuration for Linux

1, What is DHCP service DHCP (Dynamic Host Configuration Protocol) is a LAN network protocol. It refers to a range of IP addresses controlled by the server. When the client logs in to the server, it can automatically obtain the IP address and subnet mask assigned by the server. By default, DHCP, as a service component of Windows Server, wi ...

Posted by Chris_Evans on Tue, 28 Sep 2021 22:15:51 +0200

How to use esp32cam module to transmit the camera picture to raspberry pie display (based on UDP)

catalogue 1. Car end camera and wifi initialization 2. Create a UDP connection three   The car takes pictures and transmits images 4. Raspberry sends back the control command to the esp32 trolley Recently, we want to develop a picture transmission car. First, use the simplest and easiest hardware, esp32cam from AI thinker, as the ima ...

Posted by DaveMate on Thu, 23 Sep 2021 07:41:42 +0200

java network programming connection client and server small demo

(using IDEA) When connecting client and server according to the novice bird tutorial Newbie tutorial, simple client-to-server connection demo (https://www.runoob.com/java/java-networking.html) Some problems have been encountered: 1. Start by creating two java files, Client and Server, in the newly created java project. (Files with two class suf ...

Posted by daveoliveruk on Wed, 08 Sep 2021 20:10:23 +0200