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Linux driver Character device driver framework Character device is a device that reads and writes bytes one by one according to the byte stream, and the data is read and written in order. For example, our most common lighting, keys, IIC, SPI, LCD, etc. are character devices. The drivers of these devices are called character device drivers. ...

Linux Routing and Policy Routing OSI seven-tier reference model Routing Introduce Layer 2 switch, Layer 3 route: The exchange is located in the second layer of the OSI seven-layer model, where the data frame is encapsulated in an Ethernet header that records the mac address of the target network. Routing is located in the third layer of ...

Vim vim filename When on, it is command mode. // filename is opened when it exists, and created and opened when it does not exist gg Is to go directly to the top of the file content, shift + g Directly to the bottom of the file. dd Delete the line where the cursor is located 3dd Delete the line where the cursor is located and the follow ...

1. Preparation 1) Use the client tool (secureCRT or xshell) to connect to the linux server. It is recommended to open multiple servers at the same time and send the same command to multiple servers at the same time. 2. Production key file 2) Edit the hosts file on each server: vi / etc/hosts 3) Add the following contents to the document (th ...

Please visit the original link: https://sysin.org/blog/centos... , see the latest version. Original works, please keep the source for reprint.Author: GC (at) sysin Org, home page: www.sysin.orgIn daily use, the server has two IP addresses, configuration of two network cards, and access to different network segments. This is very common. However ...

Linux Log System The rsyslogd daemon can receive both user process output logs and kernel logs. The user process generates the system log by calling the syslog function. This function outputs the log to a UNIX local domain socket type (AF_UNIX) file / dev/log, and rsyslogd listens to the file to obtain the output of the user process. The kern ...

1. Purpose of task priority table The priority table is used to indicate whether there are ready tasks under the corresponding priority. The operating system kernel always selects the task execution from the highest priority in the priority table, and the ready table is dynamically updated. For example, let's understand the task priority table ...

Linux installation jdk and Tomcat 1. Install jdk 1. View the JDK package that comes with the system Command: rpm-qa | grep Java Delete the three packages pointed at by the arrow Delete native JDK Command: rpm-e --nodeps +package name Screenshot shows that it has been deleted 3. Install jdk Create a folder to load the jdk package in th ...

Primary comprehensive application of python -- student information management system Variable process control function module Project requirements: Realize the addition, deletion, modification, query and exit of the business card. Select different functions by selecting different numbers. The user's name, telephone, QQ email can be modified ...

preface RAID is to combine multiple independent physical hard disks in different ways to form a hard disk group (logical hard disk), so as to provide higher storage performance and data backup technology than a single hard disk 1, RAID disk array introduction It is the abbreviation of Redundant Array of Independent Disks, which is c ...