Article Categories
- All Categories
-
Data Structure
-
Networking
-
RDBMS
-
Operating System
-
Java
-
MS Excel
-
iOS
-
HTML
-
CSS
-
Android
-
Python
-
C Programming
-
C++
-
C#
-
MongoDB
-
MySQL
-
Javascript
-
PHP
-
Economics & Finance
Operating System Articles
Page 29 of 171
Major Activities of an Operating System with Regard to Process Management
Process management is one of the most critical functions of an operating system. A process is an active program under execution, containing program code, program counter, process stack, registers, and other execution context. The OS performs several key activities to manage processes efficiently, including process scheduling and context switching. Process Scheduling The operating system uses multiple scheduling queues to organize and manage processes at different stages of execution. When processes enter the system, they are placed in the job queue. Processes ready to execute in main memory are kept in the ready queue, while those waiting for I/O ...
Read MorecURL Command Without Using Cache
cURL (Client URL) is a command-line tool that allows data to be transferred to or from a server without requiring user interaction by utilizing the supported libcurl library. cURL can also be used to troubleshoot network connections and test web services. In some cases, we may need to send requests that bypass the cache and generate a fresh response from the server. Caching can occur on the client side (browser cache) or the server side. When using the cURL command, remember that it is only an HTTP client and does not cache any requests on the client side. As ...
Read MoreHow to Add a String After Each Line in a File in Linux?
We occasionally need to make changes to files quickly, preferably from the command line. One common task is adding a string to the end of each line of a file. In this article, we'll explore several methods to accomplish this using various Linux commands. We'll use a sample file called language.txt throughout this article. Let's first create and populate this file − $ touch language.txt $ cat > language.txt Hindi English Chinese Spanish ^D Our goal is to append the phrase "is a good language to learn" to the end of each line in the ...
Read MoreWhat is user-defined signal handler?
User-defined signal handlers are custom functions that programmers write to override the default behavior when specific signals occur in a program. Signals are software interrupts sent to indicate important events, and they can be handled in two ways: using default signal handlers or user-defined signal handlers. Types of Signal Handlers Default signal handler − Built-in system behavior for each signal type User-defined signal handler − Custom function written by the programmer to handle specific signals User-defined signal handlers allow programs to customize their response to signals rather than relying on default system actions. Different signals ...
Read MoreHow to encrypt a large file using openssl?
OpenSSL is a powerful cryptographic toolkit that provides various security functions including file encryption. It comes pre-installed on most Linux distributions, but can be installed via package managers if needed. This article demonstrates how to encrypt large files using OpenSSL's public-key cryptography features. Understanding Encryption Types Before diving into file encryption, it's important to understand the two main encryption approaches: Symmetric (Secret-key) encryption − Uses the same key for both encryption and decryption Asymmetric (Public-key) encryption − Uses separate keys for encryption and decryption Public-key encryption is more secure as it eliminates key-sharing concerns, ...
Read MoreMajor Activities of an Operating System with Regard to Memory Management
Memory management is one of the most critical functions of an operating system. It handles the allocation and deallocation of memory space to processes, manages the movement of processes between primary memory (RAM) and secondary storage (disk), and ensures optimal utilization of available memory resources. The major activities of an operating system with regard to memory management include memory allocation, swapping, paging, and segmentation. Each technique serves specific purposes in managing system memory efficiently. Memory Allocation Memory allocation involves assigning available memory blocks to processes that request them. The operating system uses various algorithms to determine which ...
Read MoreHow to swap two files in Linux command line?
As system administrators or DevOps professionals, we often need to exchange file contents. For example, you might have a backup file /etc/passwd.backup that you want to restore to /etc/passwd, while preserving the current content by moving it to the backup file. This operation is called file swapping − exchanging the actual content of two files, not their locations. When we talk about swapping two files on Linux, we mean exchanging their content while keeping their names and locations unchanged. This tutorial demonstrates practical methods to accomplish this task using command line tools. Example Files Setup Let's create ...
Read MoreWhat is default signal handler?
Signals are software interrupts sent to a program to indicate that an important event has occurred. Every signal in Unix-like operating systems can be handled by one of two possible handlers: A default signal handler A user-defined signal handler A Default signal handler is a predefined handler associated with every signal that the kernel automatically invokes when a process receives that signal. When a program doesn't specify custom handling for a particular signal, the operating system uses the default handler to perform a predetermined action. Types of Default Actions Default signal handlers can perform ...
Read MoreHow to write Stdout to a file with colors?
When working with command-line tools that produce colorized output, preserving these colors when redirecting to files can be challenging. By default, most programs detect when their output is redirected and strip away ANSI color codes. This article covers various methods to capture colored terminal output in files while maintaining the original formatting. Using Grep with Color Preservation The grep command searches for text patterns using regular expressions. To preserve colors when redirecting output, use the --color=always option. Syntax $ grep [options] pattern [files] Example First, create a sample file and then use ...
Read MoreMajor Activities of an Operating System with Regard to Secondary Storage Management
Secondary storage devices are non-volatile devices where data is stored for long-term storage. Disks are the mainly used secondary storage devices, providing the bulk of secondary storage in modern operating systems. The main activity performed in secondary storage management is disk scheduling. This involves determining the order in which disk I/O requests are serviced to minimize seek time and optimize performance. There are many disk scheduling algorithms, with the most important being FCFS, SSTF, SCAN, and LOOK scheduling. Disk Scheduling Overview Disk Track (0 to 199) ...
Read More