Introduction Semaphores were introduced by Edsger Dijkstra and are commonly used in operating systems and concurrent programming. Definition Semaphores provide a mechanism for coordinating concurrent processes or threads and protecting shared resources from simultaneous access, thereby avoiding race conditions and ensuring orderly execution. In computer science, a semaphore is a Read more…
A critical section in an operating system is a section of code that must be executed automatically, i.e., it must be completed without interruption from other processes or threads. It cannot be interrupted by other threads or processes. In an operating system (OS), a critical section refers to a portion Read more…
Definition A Scheduler/Process Schedular is an operating system program (or module) that performs process scheduling i.e. selects/sets the next job to be submitted in the ready queue for execution. Features The main function/objective of a schedular is to process scheduling for processing the job. Types There are three types of Read more…
Introduction It is also called Process Table/Task Control Block/Switch Frame. Definition Process control block(PCB) is a data structure (actually in the form of array of structure) which contains several necessary information regarding the executing processes in tabular form. Features It is maintained by an OS automatically during program execution. A Read more…
Process State/Model : Introduction A process is defined as an entity . As we know that, a process is an independent entity which represents the basic unit of work to be implemented in the system and with its own input values, output values, and internal state. A process often needs Read more…
LINKS FOR MORE DOS TRICKS History DOS (Disk Operating System) was developed by Microsoft Inc. and released it as IBM PC DOS (known as MS-DOS) for the first time on August 21, 1981, as MS-DOS 1.0, which was written by Tim Paterson. It was last updated in April 1994 when MS-DOS 6.22 Read more…
Introduction The evolution of operating systems (OS) can be traced back to the early days of computing when the first computers were designed for specific purposes and were operated by engineers and technicians. The evolution of operating systems (OS) can be traced back to the 1950s when the first mainframe Read more…
Standard/Communication Standard A standard is a broad and general term. A standard is a set of specifications(guidelines) for hardware or software used in the making of products, agreed upon by a national or international authority, or recognised body, or by general consent, or academic body, or industry group, etc. A Read more…
Type of Internet Connection/Access Method Click this link for ISP details There are several ways of connecting to access the Internet. These connections vary in techniques, speed, way of connections, use purpose, etc. These are – (A) Dial Up Connection Dial-up is rare now and hence less used. It was Read more…
Introduction of Magnetic Disk Magnetic disk consists of Magnetic Oxide materials. A modern computer uses two types of magnetic memory or disks: – Magnetic Disks: Magnetic disks are the most common form of non-volatile secondary storage because they provide fast access and high storage capacities at a reasonable cost. Examples Read more…