In the last article, we shared the commands related to linux file operations. I believe that compatriots who have read it carefully will insist on continuing to watch this piece. This article will share commands related to linux directory operations The introduction here may not be so comprehensive, so it summarizes 9 commonly used commands, …
[ linux ] Detailed explanation of linux directory operation Read More »
September 3, 2020, the 2020-2021 operating system exam for the second semester of the second semester of the School of Software, Shandong University Affected by the epidemic, the exam that should have been held in late June was changed to the exam in the first week of next semester All questions are determined according to …
Shandong University Software College Operating System (Exam) – Final Exam Recall Edition Read More »
1. Explanation of basic concepts Process synchronization: During the execution of multiple processes, the coordination of execution order in order to share resources and cooperate with each other. Also talk about mutual exclusion: when a process accesses a resource, other processes are not allowed to access it at the same time. This restriction is called …
Let’s take an example: at the beginning, the number of remaining resources is 2, and the waiting [queue] is null . Let’s look at the process. The process is from left to right: Then switch to the P1 process At this time, vlaue is equal to 0, the resource is used up, and no process …
Operating System – Illustrating the flow of recorded semaphores Read More »
[Create a new Ubuntu] virtual machine in VirtualBox under Windows system and use WindTerm and XShell to connect remotely (2022.5.11) 1. Introduction to Ubuntu system 2. Install Ubuntu system in VirtualBox virtual machine 2.1 Introduction to VirtualBox 2.2 Install VirtualBox 2.3 Download the Ubuntu image and install it in VirtualBox 3. Remotely connect to Ubuntu …
**All rights reserved, please indicate the source when reprinting, thank you! [We all know that the malloc function needs to be called to dynamically apply for memory] in the C language, and the free function needs to be called to release the dynamic memory. The application and release of memory are performed on the heap. …
Application and release of heap memory under Windows Read More »
After the server is configured with the [Ubuntu] system and the LNMP environment, if you want to use WINSCP to log in remotely, you need to enable the SSH service to support it. [SSH] service is divided into client and server. As the name suggests, I want to use WINSCP to remotely log into the …
Ubuntu opens the SSH service and allows remote login with ROOT privileges Read More »
The source is different for each version, If the source version is different, there will be a lot of errors, such as gcc missing dependencies, etc. First open the terminal and enter deb http://mirrors.aliyun.com/ubuntu/ codename main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ codename main restricted universe multiverse deb http://mirrors.aliyun.com/ubuntu/ codename-security main restricted universe multiverse deb-src http://mirrors.aliyun.com/ubuntu/ …
Ubuntu full version universal source change tutorial Read More »
The producer-consumer problem is an interdependence problem caused by multiple processes sharing a buffer . Specifically, the producer process often needs to put content in the shared buffer, and the consumer process fetches content from the shared buffer. When the buffer is full , the producer needs to wait for the consumer to take the …
Operating System – Producer Consumer Model and Semaphores Read More »
Generally speaking, in order to facilitate the linking of tools such as Xshell, we generally need to set the physical machine to a fixed IP address. Here I will use [CentOS7] in VMware to simulate this process. 1. View the virtual machine network connection mode Right-click the virtual machine → \rightarrow →set up → \rightarrow …