Document
... Typically written in a high-level language (C or C++) Mostly accessed by programs via a high-level ...
... Typically written in a high-level language (C or C++) Mostly accessed by programs via a high-level ...
PPT
... or networked computer system may want to control use of that information, concurrent processes should not interfere with each other ...
... or networked computer system may want to control use of that information, concurrent processes should not interfere with each other ...
File System Maintenance (continued)
... • Basic rules for creating a file structure: – different versions of software in their own directories – data files in directories on the basis of their functions – Design home directories to match the functions of users in an organization – Group files with similar security needs ...
... • Basic rules for creating a file structure: – different versions of software in their own directories – data files in directories on the basis of their functions – Design home directories to match the functions of users in an organization – Group files with similar security needs ...
An introduction to operating systems
... when executing an I/O instruction, should wait for the device, very slow compared to the processor speed, to complete the operation. This led to the engineers of the time to devise strategies for a more efficient use of the CPU. By loading multiple programs in memory, when a program needed to wait f ...
... when executing an I/O instruction, should wait for the device, very slow compared to the processor speed, to complete the operation. This led to the engineers of the time to devise strategies for a more efficient use of the CPU. By loading multiple programs in memory, when a program needed to wait f ...
Operating System Structures - McMaster Computing and Software
... However, lower level task written in assembly. Accessed by programs via a high-level Application Programming Interface (API) rather than direct system call use ...
... However, lower level task written in assembly. Accessed by programs via a high-level Application Programming Interface (API) rather than direct system call use ...
C Programming under Linux
... The origins of Linux are in an operating system called UNICS c. 1969. This system developed into UNIX through the 70s – in parallel with a new programming language written for its operating system, C. Unix was developed initially on hugely expensive computers costing millions of $, £ or Euros. Unix ...
... The origins of Linux are in an operating system called UNICS c. 1969. This system developed into UNIX through the 70s – in parallel with a new programming language written for its operating system, C. Unix was developed initially on hugely expensive computers costing millions of $, £ or Euros. Unix ...
Operating Systems Introduction
... code and user defined code. • The approach taken by most computer systems is to provide hardware support that allows us to differentiate among various modes of execution. ...
... code and user defined code. • The approach taken by most computer systems is to provide hardware support that allows us to differentiate among various modes of execution. ...
Lecture 15 - Department of Math and Computer Science
... First developed as a small but self-contained kernel in 1991 by ...
... First developed as a small but self-contained kernel in 1991 by ...
The Nachos Instructional Operating System
... connect Nachos \machines", each running as a UNIX process, together via UNIX sockets, simulating a local area network. A thread on one \machine" can then send a packet to a thread running on a di erent \machine"; of course, both are simulated on the same physical hardware. Our simulation is determin ...
... connect Nachos \machines", each running as a UNIX process, together via UNIX sockets, simulating a local area network. A thread on one \machine" can then send a packet to a thread running on a di erent \machine"; of course, both are simulated on the same physical hardware. Our simulation is determin ...
Introduction - Computer Science
... reliability: what happens if something goes wrong – hardware or software extensibility: can we add new features? communication: how do programs exchange information concurrency: how are parallel activities created and controlled? scale: what happens as demands or resources increase? persistence: how ...
... reliability: what happens if something goes wrong – hardware or software extensibility: can we add new features? communication: how do programs exchange information concurrency: how are parallel activities created and controlled? scale: what happens as demands or resources increase? persistence: how ...
2. Operating System Case Study: Linux
... for minicomputer for commercial applications People was looking for a UNIX based system, which i cheaper is h and d can run on PC Both DOS, MAC and UNIX are proprietary, i.e., the protected source code of their kernel is p – No modification is possible without paying high license fees ...
... for minicomputer for commercial applications People was looking for a UNIX based system, which i cheaper is h and d can run on PC Both DOS, MAC and UNIX are proprietary, i.e., the protected source code of their kernel is p – No modification is possible without paying high license fees ...
交大資工蔡文能計概
... Early UNIX History (4/4) • In Version 6, the source code of UNIX was 8200 lines of C and 900 lines of assembler. • The first portable version arrived with Version 7 which had 18,800 lines of C and 2100 lines of assembly instruction. • By the 1980s the use of UNIX was widespread with many vendors se ...
... Early UNIX History (4/4) • In Version 6, the source code of UNIX was 8200 lines of C and 900 lines of assembler. • The first portable version arrived with Version 7 which had 18,800 lines of C and 2100 lines of assembly instruction. • By the 1980s the use of UNIX was widespread with many vendors se ...
Course Introduction
... OS History – Unix & Linux • Unix – Descendant of MULTICS – First “C” version in 1973 (DEC PDP-11) • Timesharing for < 10 users on 32K Memory • Many Unix versions at BTL – different goals • Source code made available to Universities – BSD ...
... OS History – Unix & Linux • Unix – Descendant of MULTICS – First “C” version in 1973 (DEC PDP-11) • Timesharing for < 10 users on 32K Memory • Many Unix versions at BTL – different goals • Source code made available to Universities – BSD ...
CSc 352: Systems Programming & Unix
... lists the files in a directory one screenful at a time How this works: • ls writes its output to its stdout • more’s input stream defaults to its stdin • the pipe connects ls’s stdout to more’s stdin • the piped commands run “in parallel” ...
... lists the files in a directory one screenful at a time How this works: • ls writes its output to its stdout • more’s input stream defaults to its stdin • the pipe connects ls’s stdout to more’s stdin • the piped commands run “in parallel” ...
UNIX I
... ret may be less than len e.g. if OS buffers full * should really check and repeat until all gone * ¥ buff need not be NULL terminated if buff is a C string, use strlen to get its length N.B. Both may return negative after interrupt (signal) ...
... ret may be less than len e.g. if OS buffers full * should really check and repeat until all gone * ¥ buff need not be NULL terminated if buff is a C string, use strlen to get its length N.B. Both may return negative after interrupt (signal) ...
What Is Linux? - Kendriya Vidyalaya Central Railway
... In popular usage, “Linux is an operating system.” ,however, the strictest definition of Linux is only the kernel. The more relaxed definition would be an overall package called a distribution that is ready to install and use. There are well over 300 distributions of Linux, most of them containing co ...
... In popular usage, “Linux is an operating system.” ,however, the strictest definition of Linux is only the kernel. The more relaxed definition would be an overall package called a distribution that is ready to install and use. There are well over 300 distributions of Linux, most of them containing co ...
Lecture #3: Operating
... systems) can share the same hardware Protect from each other Some sharing of file can be permitted, controlled Commutate with each other, other physical systems via networking Useful for development, testing Consolidation of many low-resource use systems onto fewer busier systems “Open V ...
... systems) can share the same hardware Protect from each other Some sharing of file can be permitted, controlled Commutate with each other, other physical systems via networking Useful for development, testing Consolidation of many low-resource use systems onto fewer busier systems “Open V ...
2.01
... Although MS-DOS has some structure, its interfaces and levels of functionality are not well separated ...
... Although MS-DOS has some structure, its interfaces and levels of functionality are not well separated ...
Guide-to-UNIX-Using-Linux-4th-Edition-Michael-Palmer-Test-Bank
... insulation, ensuring system security and user privacy. The kernel is the base operating system, and it interacts directly with the hardware, software services, application programs, and user-created scripts (which are files containing commands to execute). It is accessible only through Kernel mode, ...
... insulation, ensuring system security and user privacy. The kernel is the base operating system, and it interacts directly with the hardware, software services, application programs, and user-created scripts (which are files containing commands to execute). It is accessible only through Kernel mode, ...
Basic Unix - University of Arizona
... lists the files in a directory one screenful at a time How this works: • ls writes its output to its stdout • more’s input stream defaults to its stdin • the pipe connects ls’s stdout to more’s stdin • the piped commands run “in parallel” ...
... lists the files in a directory one screenful at a time How this works: • ls writes its output to its stdout • more’s input stream defaults to its stdin • the pipe connects ls’s stdout to more’s stdin • the piped commands run “in parallel” ...
2.01 - Faculty of Computer Science and Information Technology
... Apple Mac OS X as “Aqua” GUI interface with UNIX kernel underneath and shells available ...
... Apple Mac OS X as “Aqua” GUI interface with UNIX kernel underneath and shells available ...
Linux Operating System
... You may have previous experience with MSDOS or other single user operating systems, such as OS/2 or the Macintosh. In these operating systems, you didin’t have to identify yourself to the computer before using it; it was assumed that you were the only user of the system and could access everything. ...
... You may have previous experience with MSDOS or other single user operating systems, such as OS/2 or the Macintosh. In these operating systems, you didin’t have to identify yourself to the computer before using it; it was assumed that you were the only user of the system and could access everything. ...
Unix
Unix (all-caps UNIX for the trademark) is a family of multitasking, multiuser computer operating systems that derive from the original AT&T Unix, developed in the 1970s at the Bell Labs research center by Ken Thompson, Dennis Ritchie, and others.Initially intended for use inside the Bell System, AT&T licensed Unix to outside parties from the late 1970s, leading to a variety of both academic and commercial variants of Unix from vendors such as the University of California, Berkeley (BSD), Microsoft (Xenix), IBM (AIX) and Sun Microsystems (Solaris). AT&T finally sold its rights in Unix to Novell in the early 1990s, which then sold its Unix business to the Santa Cruz Operation (SCO) in 1995, but the UNIX trademark passed to the industry standards consortium The Open Group, which allows the use of the mark for certified operating systems compliant with the Single UNIX Specification (SUS). Among these is Apple's OS X, which is the Unix version with the largest installed base as of 2014.From the power user's or programmer's perspective, Unix systems are characterized by a modular design that is sometimes called the ""Unix philosophy"", meaning that the operating system provides a set of simple tools that each perform a limited, well-defined function, with a unified filesystem as the main means of communication and a shell scripting and command language to combine the tools to perform complex workflows. Aside from the modular design, Unix also distinguishes itself from its predecessors as the first portable operating system: almost the entire operating system is written in the C programming language that allowed Unix to reach numerous platforms.Many clones of Unix have arisen over the years, of which Linux is the most popular, having overtaken the popularity of SUS-certified Unices on server platforms since its inception in the early 1990s.