1.1. The UNIX Operating System
... attempt UNICS (Uniplexed Information and Computing System). Because memory and CPU power were at a premium in those days, UNICS (eventually shortened to UNIX) used short commands to minimize the space needed to store them and the time needed to decode them - hence the tradition of short UNIX command ...
... attempt UNICS (Uniplexed Information and Computing System). Because memory and CPU power were at a premium in those days, UNICS (eventually shortened to UNIX) used short commands to minimize the space needed to store them and the time needed to decode them - hence the tradition of short UNIX command ...
ngOS01 OS Architecture
... • Microkernel to cope with the ever increasing complexity of the UNIX operating system – Reduce the number of features in the kernel to make it less complex ...
... • Microkernel to cope with the ever increasing complexity of the UNIX operating system – Reduce the number of features in the kernel to make it less complex ...
Operating Systems - Computer Science
... time. Functions that were originally part of the operating system have migrated to the hardware. On the other side, programmed functions extraneous to the problems being solved by the application programs are included in the operating system. ...
... time. Functions that were originally part of the operating system have migrated to the hardware. On the other side, programmed functions extraneous to the problems being solved by the application programs are included in the operating system. ...
System
... • Many services traditionally included in the OS kernel are now external subsystems – device drivers, file systems, virtual memory manager, windowing system, security services ...
... • Many services traditionally included in the OS kernel are now external subsystems – device drivers, file systems, virtual memory manager, windowing system, security services ...
Chapter 1: Operating System Concepts
... There are several design goals in building an operating system, for example, resource utilization, timeliness, robustness, etc. Give an example of two design goals that may contradict one another. Consider the goals of fairness and real time. Fairness requires that each process be allocated its reso ...
... There are several design goals in building an operating system, for example, resource utilization, timeliness, robustness, etc. Give an example of two design goals that may contradict one another. Consider the goals of fairness and real time. Fairness requires that each process be allocated its reso ...
ppt - Dave Reed
... layered approach: OS is divided into distinct layers bottom layer = hardware; highest layer = user interface layers are selected such that each uses functions and services of adjacent layers advantage: modularity simplifies development & debugging disadvantages: requires careful definition of la ...
... layered approach: OS is divided into distinct layers bottom layer = hardware; highest layer = user interface layers are selected such that each uses functions and services of adjacent layers advantage: modularity simplifies development & debugging disadvantages: requires careful definition of la ...
Overview and History
... layered approach: OS is divided into distinct layers bottom layer = hardware; highest layer = user interface layers are selected such that each uses functions and services of adjacent layers advantage: modularity simplifies development & debugging disadvantages: requires careful definition of la ...
... layered approach: OS is divided into distinct layers bottom layer = hardware; highest layer = user interface layers are selected such that each uses functions and services of adjacent layers advantage: modularity simplifies development & debugging disadvantages: requires careful definition of la ...
Sai Uday Kiran Ravi`s presentation on Application Security on
... File metadata needs to be protected, including file names, sizes, and modification times. Attack: A malicious OS could perform a pathname lookup incorrectly. Even a system that protects file contents may be subverted if the OS redirects a request for a protected file to a different but still valid p ...
... File metadata needs to be protected, including file names, sizes, and modification times. Attack: A malicious OS could perform a pathname lookup incorrectly. Even a system that protects file contents may be subverted if the OS redirects a request for a protected file to a different but still valid p ...
Operating Systems
... operating system have migrated to the hardware. On the other side, programmed functions extraneous to the problems being solved by the application programs are included in the operating system. ...
... operating system have migrated to the hardware. On the other side, programmed functions extraneous to the problems being solved by the application programs are included in the operating system. ...
COS 318: Operating Systems Introduction Kai Li Computer Science Department
... It is “magic” to realize what we want It gives us “power” ...
... It is “magic” to realize what we want It gives us “power” ...
CUSTOMER_CODE SMUDE DIVISION_CODE SMUDE
... UNIX allows them to be used in much the same way as ordinary files. There are two types of devices in UNIX- block-oriented devices which transfer data in blocks and character – oriented devices that transfer data on a byte-by – byte basis. ii.Links: A link is a pointer to another file. There are two ...
... UNIX allows them to be used in much the same way as ordinary files. There are two types of devices in UNIX- block-oriented devices which transfer data in blocks and character – oriented devices that transfer data on a byte-by – byte basis. ii.Links: A link is a pointer to another file. There are two ...
What is an Operating System?
... Guarantees critical tasks completed on time. Delays in system must be bounded. No virtual memory, limited use of secondary storage, no time-sharing. Eg. VxWorks ...
... Guarantees critical tasks completed on time. Delays in system must be bounded. No virtual memory, limited use of secondary storage, no time-sharing. Eg. VxWorks ...
Slide 2: Operating System Overview
... time. Functions that were originally part of the operating system have migrated to the hardware. On the other side, programmed functions extraneous to the problems being solved by the application programs are included in the operating system. ...
... time. Functions that were originally part of the operating system have migrated to the hardware. On the other side, programmed functions extraneous to the problems being solved by the application programs are included in the operating system. ...
History of Unix OS - Seneca
... The Unix OS was developed (based on Multics & CTSS operating systems) by Ken Thompson at the AT&T Bell Laboratories in 1969. He wanted to create an multi-user operating system to run “space wars” game. Ken’s philosophy was to create an operating system with commands or “utilities” that would do one ...
... The Unix OS was developed (based on Multics & CTSS operating systems) by Ken Thompson at the AT&T Bell Laboratories in 1969. He wanted to create an multi-user operating system to run “space wars” game. Ken’s philosophy was to create an operating system with commands or “utilities” that would do one ...
Operating System Structures
... The system call interface invokes intended system call in OS kernel and returns status of the system call and any return values • The caller need know nothing about how the system call is implemented ...
... The system call interface invokes intended system call in OS kernel and returns status of the system call and any return values • The caller need know nothing about how the system call is implemented ...
OPERATING SYSTEM
... might be from program 1, the next few from program 2, then some from program 3, and so forth. The result would be chaos. The operating system can bring order to the potential chaos by buffering all the output destined for the printer on the disk. When one program is finished, the operating system ca ...
... might be from program 1, the next few from program 2, then some from program 3, and so forth. The result would be chaos. The operating system can bring order to the potential chaos by buffering all the output destined for the printer on the disk. When one program is finished, the operating system ca ...
pptx
... An early capability-based, object-oriented, microkernel implemented in the programming language BLISS as part of the C.mmp project at Carnegie-Mellon University ...
... An early capability-based, object-oriented, microkernel implemented in the programming language BLISS as part of the C.mmp project at Carnegie-Mellon University ...
lecture1
... the kernel. Some older operating systems had a rendezvous style of providing these services - the process would request a service and wait at a particular point, until a kernel task came along and serviced the request on behalf of the process. UNIX works very differently. Rather than having kernel t ...
... the kernel. Some older operating systems had a rendezvous style of providing these services - the process would request a service and wait at a particular point, until a kernel task came along and serviced the request on behalf of the process. UNIX works very differently. Rather than having kernel t ...
Operating Systems
... For batch processing, a user asks the shell to run a special type of program called “script” to execute a sequence of programs For interactive processing, a user uses a keyboard, a mouse, and tablets, etc. to issue commands to the shell and input data into a computer ...
... For batch processing, a user asks the shell to run a special type of program called “script” to execute a sequence of programs For interactive processing, a user uses a keyboard, a mouse, and tablets, etc. to issue commands to the shell and input data into a computer ...
QUIZ1
... 8. Discuss what CPU must do (a) when the current process exits it, (b) when it has to respond to an interrupt, or (c) the triggering event is a trap. 9. An OS could appear in different architectural modes like monolithic, layered, objected oriented and as a micro-kernel. Indicate their basic design ...
... 8. Discuss what CPU must do (a) when the current process exits it, (b) when it has to respond to an interrupt, or (c) the triggering event is a trap. 9. An OS could appear in different architectural modes like monolithic, layered, objected oriented and as a micro-kernel. Indicate their basic design ...
Unix File System
... In addition to the classic Data Encryption Standard (DES), there is an advanced symmetric-key encryption algorithm AES (Advanced Encryption Standard). The AES-128, AES-192 and AES-256 use a 128-bit block size, with key sizes of 128, 192 and 256 bits, respectively Most linux systems use Hash Function ...
... In addition to the classic Data Encryption Standard (DES), there is an advanced symmetric-key encryption algorithm AES (Advanced Encryption Standard). The AES-128, AES-192 and AES-256 use a 128-bit block size, with key sizes of 128, 192 and 256 bits, respectively Most linux systems use Hash Function ...
Chapter 1 - OS Overview
... efficiency with which a computer system meets its goals” - how well it serves it users • A system’s efficiency is affected by 3 major components: – the user’s programs – operating system programs ...
... efficiency with which a computer system meets its goals” - how well it serves it users • A system’s efficiency is affected by 3 major components: – the user’s programs – operating system programs ...
Lecture 1: Operating System Services What is an Operating System?
... Interrupt handling: Operating systems are event driven programs. If there are no programs to execute, no I/O devices to service, and no user to respond to, an O.S. will sit quietly, waiting for something to happen. Events are almost always signaled by the occurrence of an interrupt or trap. When an ...
... Interrupt handling: Operating systems are event driven programs. If there are no programs to execute, no I/O devices to service, and no user to respond to, an O.S. will sit quietly, waiting for something to happen. Events are almost always signaled by the occurrence of an interrupt or trap. When an ...