Chapter 1 Intro to Java
... History of Java • Java – Originally for intelligent consumer-electronic devices – Then used for creating Web pages with dynamic content – Now also used to: • Develop large-scale enterprise applications • Enhance WWW server functionality • Provide applications for consumer devices (cell phones, etc.) ...
... History of Java • Java – Originally for intelligent consumer-electronic devices – Then used for creating Web pages with dynamic content – Now also used to: • Develop large-scale enterprise applications • Enhance WWW server functionality • Provide applications for consumer devices (cell phones, etc.) ...
CS101 Spring 2012 LHC32
... These variables are not defined magically To use them, must prefix our C++ code with instruction to include a header file like this: #include
The operating system and compiler work
together to let your code access the
keyboard and display through cin and cout
Not quite…
CS101 2012 ...
... These variables are not defined magically To use them, must prefix our C++ code with instruction to include a header file like this: #include
Deployment of Sensing Devices on Critical Infrastructure
... Software categories • Applications software • Systems software •What is an operating system? ...
... Software categories • Applications software • Systems software •What is an operating system? ...
Lecture 5 - Rabie A. Ramadan
... Software categories • Applications software • Systems software •What is an operating system? ...
... Software categories • Applications software • Systems software •What is an operating system? ...
CS 570-Advanced Operating Systems-Junaid
... This course introduces advanced operating system topic sand introduces recent developments in systems research. The course involves reading and understanding classic and new research papers on operating systems. Topics include operating system structure, threads and synchronization, virtual memory ...
... This course introduces advanced operating system topic sand introduces recent developments in systems research. The course involves reading and understanding classic and new research papers on operating systems. Topics include operating system structure, threads and synchronization, virtual memory ...
Introduction to Programming
... Finding the lines of code that cause the error Fixing the code Testing to check if the error is gone and no errors are introduced Iterative and continuous process ...
... Finding the lines of code that cause the error Fixing the code Testing to check if the error is gone and no errors are introduced Iterative and continuous process ...
Chapter 1 – Introduction to Computers and C++ Programming
... – Evolved in 1972 by Ritchie from two previous programming languages, BCPL and B – Used to develop UNIX – Now, most operating systems written with C or C++ – Hardware independent (portable) – By late 1970's C had evolved to "Traditional C" ...
... – Evolved in 1972 by Ritchie from two previous programming languages, BCPL and B – Used to develop UNIX – Now, most operating systems written with C or C++ – Hardware independent (portable) – By late 1970's C had evolved to "Traditional C" ...
L03_Processes
... operating system is divided into a number of layers or levels, each built on top of lower layers. The lowest layer is the hardware; the highest is the user interface. Layers are selected such that each uses functions and services of only lower-level layers. ...
... operating system is divided into a number of layers or levels, each built on top of lower layers. The lowest layer is the hardware; the highest is the user interface. Layers are selected such that each uses functions and services of only lower-level layers. ...
Training
... Subject Outline (continue) Passing grade and Grade Distribution (Guidelines) • A (0% - 20%) • A+B (40% - 75%) • C, D, E, F (25% - 60%) • Average of this class should be either B- or C+. • To pass this subject, the final exam should be >= 30. • To pass this subject, the overall score should be >= 35 ...
... Subject Outline (continue) Passing grade and Grade Distribution (Guidelines) • A (0% - 20%) • A+B (40% - 75%) • C, D, E, F (25% - 60%) • Average of this class should be either B- or C+. • To pass this subject, the final exam should be >= 30. • To pass this subject, the overall score should be >= 35 ...
Protection of System Resources
... instruction. Count set to –1 if call failed or to number of bytes actually read if successful. Step 10. Library procedure returns to user program. Step 11. User program resets stack pointer to clean up library call. ...
... instruction. Count set to –1 if call failed or to number of bytes actually read if successful. Step 10. Library procedure returns to user program. Step 11. User program resets stack pointer to clean up library call. ...
The Evolution of OS
... Simple => minimize the size of the monitor. A job was always loaded into the same location => no need for relocation at load time. • Minimized disk activity. • Problems Raised: – Multiple jobs in memory => memory protection – Multiple users in the system => file protection – Contention for resources ...
... Simple => minimize the size of the monitor. A job was always loaded into the same location => no need for relocation at load time. • Minimized disk activity. • Problems Raised: – Multiple jobs in memory => memory protection – Multiple users in the system => file protection – Contention for resources ...
program
... characters, audio, video, even programs) are encoded and stored using 1s and 0s. • When more than a single byte is needed, several adjacent bytes are used. – The address of the first byte is the address of the unit of bytes. ...
... characters, audio, video, even programs) are encoded and stored using 1s and 0s. • When more than a single byte is needed, several adjacent bytes are used. – The address of the first byte is the address of the unit of bytes. ...
N4Less27.pps
... Programmers may also create a simple text version of a program's code – called pseudocode – to determine how the program will flow. ...
... Programmers may also create a simple text version of a program's code – called pseudocode – to determine how the program will flow. ...
Ch2 OS Structures 1
... storage, I/O devices. – Accounting ‐ To keep track of which users use how much and what kinds of computer resources – Protection and security ‐ The owners of information stored in a multiuser or networked computer system may want to control use of that information, concurrent processes should not ...
... storage, I/O devices. – Accounting ‐ To keep track of which users use how much and what kinds of computer resources – Protection and security ‐ The owners of information stored in a multiuser or networked computer system may want to control use of that information, concurrent processes should not ...
PDF
... 4. Threads vs. Processes The file parcount.py contains a partial implementation of a program that runs N jobs, each of which does some I/O and some processing. It uses three strategies to run the jobs: run_sequential runs them all sequentially. The run_threaded divides the jobs into n threads, each ...
... 4. Threads vs. Processes The file parcount.py contains a partial implementation of a program that runs N jobs, each of which does some I/O and some processing. It uses three strategies to run the jobs: run_sequential runs them all sequentially. The run_threaded divides the jobs into n threads, each ...
Operating System Structures
... allocate resources for multiple users or multiple jobs running concurrently ...
... allocate resources for multiple users or multiple jobs running concurrently ...
different people attempt to accomplish the
... Perl. Various Perl modules provide a framework that can be properly (or poorly) used to aid in building packages that can be tested before installation. Diomidis Spinellis has written about the effects of the many levels of performance found in modern computer memory. The amount of memory available ...
... Perl. Various Perl modules provide a framework that can be properly (or poorly) used to aid in building packages that can be tested before installation. Diomidis Spinellis has written about the effects of the many levels of performance found in modern computer memory. The amount of memory available ...
Operating Systems CMPSC 473
... • OS competes with the processes for resources – E.g., OS uses disk to swap ...
... • OS competes with the processes for resources – E.g., OS uses disk to swap ...
talk
... well-behaved environment • O.S. defines a set of logical resources (objects) and a set of well-defined operations on those objects (i.e., an interface to use those objects) • Provides mechanisms and policies for the control of objects/resources • Controls how different users and programs interact • ...
... well-behaved environment • O.S. defines a set of logical resources (objects) and a set of well-defined operations on those objects (i.e., an interface to use those objects) • Provides mechanisms and policies for the control of objects/resources • Controls how different users and programs interact • ...
distil2
... level of programming significantly raised (“what” vs “how”) more general, powerful approach larger selection of structures/mechanisms ...
... level of programming significantly raised (“what” vs “how”) more general, powerful approach larger selection of structures/mechanisms ...
Final Report
... allocated and free blocks using a bit map. A typical exercise might be for students to write a program (in Java) which invokes various simulated operating system calls against a well-known disk image provided by the instructor. Students may also be asked to implement indirect blocks, list-based free ...
... allocated and free blocks using a bit map. A typical exercise might be for students to write a program (in Java) which invokes various simulated operating system calls against a well-known disk image provided by the instructor. Students may also be asked to implement indirect blocks, list-based free ...
Chapter 2 Operating System Overview
... – Prevents a job from monopolizing the system (when allocated time is up, job is stopped) ...
... – Prevents a job from monopolizing the system (when allocated time is up, job is stopped) ...
OS Services #1 File
... jobs are running at the same time, resources must be allocated to each of them. Many different types of resources are managed by the operating system. For instance, in determining how best to use the CPU, operating systems have CPUscheduling routines that take into account the speed of the CPU, the ...
... jobs are running at the same time, resources must be allocated to each of them. Many different types of resources are managed by the operating system. For instance, in determining how best to use the CPU, operating systems have CPUscheduling routines that take into account the speed of the CPU, the ...
program - Computer Sciences User Pages
... compiles to a virtual processor that is the same for every computer Lesson: The code is the same no matter what computer you are on, so you don’t have to make a Mac version and a PC version, etc. ...
... compiles to a virtual processor that is the same for every computer Lesson: The code is the same no matter what computer you are on, so you don’t have to make a Mac version and a PC version, etc. ...
Introduction
... Main memory (stores programs and data during execution) Cache memory Fastest and most expensive form of memory, per byte Non-Volatile – contents are maintained when power is turned off: Hard drive (internal or external, stores programs and data permanently) ...
... Main memory (stores programs and data during execution) Cache memory Fastest and most expensive form of memory, per byte Non-Volatile – contents are maintained when power is turned off: Hard drive (internal or external, stores programs and data permanently) ...
Library (computing)
In computer science, a library is a collection of non-volatile resources used by computer programs, often to develop software. These may include configuration data, documentation, help data, message templates, pre-written code and subroutines, classes, values or type specifications. In IBM's OS/360 and its successors they are referred to as partitioned data sets.In computer science, a library is a collection of implementations of behavior, written in terms of a language, that has a well-defined interface by which the behavior is invoked. This means that as long as a higher level program uses a library to make system calls, it does not need to be re-written to implement those system calls over and over again. In addition, the behavior is provided for reuse by multiple independent programs. A program invokes the library-provided behavior via a mechanism of the language. For example, in a simple imperative language such as C, the behavior in a library is invoked by using C's normal function-call. What distinguishes the call as being to a library, versus being to another function in the same program, is the way that the code is organized in the system. Library code is organized in such a way that it can be used by multiple programs that have no connection to each other, while code that is part of a program is organized to only be used within that one program. This distinction can gain a hierarchical notion when a program grows large, such as a multi-million-line program. In that case, there may be internal libraries that are reused by independent sub-portions of the large program. The distinguishing feature is that a library is organized for the purposes of being reused by independent programs or sub-programs, and the user only needs to know the interface, and not the internal details of the library.The value of a library is the reuse of the behavior. When a program invokes a library, it gains the behavior implemented inside that library without having to implement that behavior itself. Libraries encourage the sharing of code in a modular fashion, and ease the distribution of the code. The behavior implemented by a library can be connected to the invoking program at different program lifecycle phases. If the code of the library is accessed during the build of the invoking program, then the library is called a static library. An alternative is to build the executable of the invoking program and distribute that, independently from the library implementation. The library behavior is connected after the executable has been invoked to be executed, either as part of the process of starting the execution, or in the middle of execution. In this case the library is called a dynamic library. A dynamic library can be loaded and linked as part of preparing a program for execution, by the linker. Alternatively, in the middle of execution, an application may explicitly request that a module be loaded.Most compiled languages have a standard library although programmers can also create their own custom libraries. Most modern software systems provide libraries that implement the majority of system services. Such libraries have commoditized the services which a modern application requires. As such, most code used by modern applications is provided in these system libraries.