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Laboratory Virtual Instrument Engineering Workbench ( LabVIEW ) is a graphical system design and development platform produced and distributed by National Instruments , based on a programming environment that uses a visual programming language . It is widely used for data acquisition , instrument control , and industrial automation . It provides tools for designing and deploying complex test and measurement systems.

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77-586: The visual (aka graphical) programming language is called "G" (not to be confused with G-code ). It is a dataflow language originally developed by National Instruments. LabVIEW is supported on a variety of operating systems (OSs), including macOS and other versions of Unix and Linux , as well as Microsoft Windows . The latest versions of LabVIEW are LabVIEW 2024 Q3 (released in July 2024) and LabVIEW NXG 5.1 (released in January 2021). National Instruments released

154-426: A control , indicator , structure , function, or recursively, another block diagram . An example of a simple four-node block diagram is two controls and an indicator wired to the addition function, causing the indicator to display the sum of the two controls. The wires connecting nodes propagate data as variables, and any node can execute as soon as all its input variables (data) become available. Since this might be

231-456: A front panel , back panel , and connector panel , all composed of nodes and wires represented graphically to the user. The front panel is built using controls and indicators. Controls are inputs, they allow a user to supply information to the VI. Indicators are outputs, they indicate or display the results based on the inputs given to the VI. The back panel consists of a block diagram containing

308-428: A system call to perform a block I/O write operation, then the system call might execute the following instructions: While the writing takes place, the operating system will context switch to other processes as normal. When the device finishes writing, the device will interrupt the currently running process by asserting an interrupt request . The device will also place an integer onto the data bus. Upon accepting

385-850: A chassis controller. Currently only NI C Series modules are compatible with the CompactDAQ platform. Modules are available with analog inputs and outputs for various sensor and signal types, digital inputs and outputs, built-in signal conditioning and ADCs , and most modules provide electrical isolation . Sensor data is collected and analyzed using compatible PC software such as LabVIEW , LabWindows/CVI , Measurement Studio and SignalExpress, also built by National Instruments. Application programming interfaces are also available for C/C++, and .NET languages such as C#. LabVIEW integrates with CompactDAQ chassis controller hardware to connect to physical sensor or signal data sources. LabVIEW can also connect to oscilloscopes and USB DAQ systems using

462-409: A compiler based on LLVM . These code chunks are called by the "G" run-time engine, providing for fast, high-performance native execution of the graphical code. The LabVIEW syntax is strictly enforced during the editing process, and when "G" code is run or saved, the compiler is automatically invoked. "G" code is saved to a single binary file that contains both the source and executable code. Execution

539-408: A completely redesigned LabVIEW NXG 1.0 built on Windows Presentation Foundation (WPF). OpenG and LAVA Code Repository (LAVAcr) serve as repositories for a wide range of Open Source LabVIEW applications and libraries . SourceForge has LabVIEW listed as one of the possible languages in which code can be written. VI Package Manager has become the standard package manager for LabVIEW libraries. It

616-645: A computer even if they are not compatible with the base operating system. A library operating system (libOS) is one in which the services that a typical operating system provides, such as networking, are provided in the form of libraries and composed with a single application and configuration code to construct a unikernel : a specialized (only the absolute necessary pieces of code are extracted from libraries and bound together ), single address space , machine image that can be deployed to cloud or embedded environments. The operating system code and application code are not executed in separated protection domains (there

693-585: A development of MULTICS for a single user. Because UNIX's source code was available, it became the basis of other, incompatible operating systems, of which the most successful were AT&T 's System V and the University of California 's Berkeley Software Distribution (BSD). To increase compatibility, the IEEE released the POSIX standard for operating system application programming interfaces (APIs), which

770-557: A free-for-non-commercial use version called LabVIEW Community Edition. This version includes everything in the Professional Editions of LabVIEW, has no watermarks, and includes the LabVIEW NXG Web Module for non-commercial use. These editions may also be used by K-12 schools. LabVIEW is a proprietary product of National Instruments. Unlike common programming languages such as C or Fortran , LabVIEW

847-484: A large legal settlement was paid. In the twenty-first century, Windows continues to be popular on personal computers but has less market share of servers. UNIX operating systems, especially Linux, are the most popular on enterprise systems and servers but are also used on mobile devices and many other computer systems. On mobile devices, Symbian OS was dominant at first, being usurped by BlackBerry OS (introduced 2002) and iOS for iPhones (from 2007). Later on,

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924-442: A library with no protection between applications, such as eCos . A hypervisor is an operating system that runs a virtual machine . The virtual machine is unaware that it is an application and operates as if it had its own hardware. Virtual machines can be paused, saved, and resumed, making them useful for operating systems research, development, and debugging. They also enhance portability by enabling applications to be run on

1001-447: A malformed machine instruction . However, the most common error conditions are division by zero and accessing an invalid memory address . Users can send messages to the kernel to modify the behavior of a currently running process. For example, in the command-line environment , pressing the interrupt character (usually Control-C ) might terminate the currently running process. To generate software interrupts for x86 CPUs,

1078-505: A marketplace for both free and paid LabVIEW add-ons, called the NI Tools Network . There is a low-cost LabVIEW Student Edition aimed at educational institutions for learning purposes. There is also an active community of LabVIEW users who communicate through several electronic mailing lists (email groups) and Internet forums . National Instruments provides a low cost LabVIEW Home Bundle Edition. National Instruments provides

1155-455: A particular application's memory is stored, or even whether or not it has been allocated yet. In modern operating systems, memory which is accessed less frequently can be temporarily stored on a disk or other media to make that space available for use by other programs. This is called swapping , as an area of memory can be used by multiple programs, and what that memory area contains can be swapped or exchanged on demand. Virtual memory provides

1232-503: A program does not interfere with memory already in use by another program. Since programs time share, each program must have independent access to memory. Cooperative memory management, used by many early operating systems, assumes that all programs make voluntary use of the kernel 's memory manager, and do not exceed their allocated memory. This system of memory management is almost never seen any more, since programs often contain bugs which can cause them to exceed their allocated memory. If

1309-408: A program fails, it may cause memory used by one or more other programs to be affected or overwritten. Malicious programs or viruses may purposefully alter another program's memory, or may affect the operation of the operating system itself. With cooperative memory management, it takes only one misbehaved program to crash the system. Memory protection enables the kernel to limit a process' access to

1386-440: A program tries to access memory that is not accessible memory, but nonetheless has been allocated to it, the kernel is interrupted (see § Memory management ) . This kind of interrupt is typically a page fault . When the kernel detects a page fault it generally adjusts the virtual memory range of the program which triggered it, granting it access to the memory requested. This gives the kernel discretionary power over where

1463-488: A set of classes for use with Microsoft Visual Studio . This allows developers to harness some of LabVIEW's strengths within the text-based .NET Framework . National Instruments also offers LabWindows/CVI as an alternative for ANSI C programmers. When applications need sequencing, users often use LabVIEW with the National Instruments TestStand test management software. The Ch interpreter

1540-470: A significant amount of CPU time. Direct memory access (DMA) is an architecture feature to allow devices to bypass the CPU and access main memory directly. (Separate from the architecture, a device may perform direct memory access to and from main memory either directly or via a bus.) When a computer user types a key on the keyboard, typically the character appears immediately on the screen. Likewise, when

1617-402: A specific moment in time. Hard real-time systems require exact timing and are common in manufacturing , avionics , military, and other similar uses. With soft real-time systems, the occasional missed event is acceptable; this category often includes audio or multimedia systems, as well as smartphones. In order for hard real-time systems be sufficiently exact in their timing, often they are just

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1694-501: A subroutine within a larger program, and the front panel controls the inputs and outputs of the VI node. Thus, each VI can be easily tested as a stand-alone program before being embedded as a subroutine into a larger program. The "G" graphical approach allows non-programmers to easily build programs by dragging and dropping virtual representations of lab equipment with which they are already familiar. The LabVIEW programming environment includes examples and documentation to guide and simplify

1771-485: A syntax that is generally compatible with MATLAB . LabVIEW is an inherently concurrent language , so it is very easy to program multiple tasks that are performed in parallel via multithreading, for example by drawing two or more parallel while loops and connecting them to two separate nodes. This provides a great benefit for test system automation, where it is common practice to run processes like test sequencing, data recording, and hardware interfacing in parallel. Due to

1848-417: A user moves a mouse , the cursor immediately moves across the screen. Each keystroke and mouse movement generates an interrupt called Interrupt-driven I/O . An interrupt-driven I/O occurs when a process causes an interrupt for every character or word transmitted. Devices such as hard disk drives , solid-state drives , and magnetic tape drives can transfer data at a rate high enough that interrupting

1925-453: A variation of the classic reader/writer problem . The writer receives a pipe from the shell for its output to be sent to the reader's input stream. The command-line syntax is alpha | bravo . alpha will write to the pipe when its computation is ready and then sleep in the wait queue. bravo will then be moved to the ready queue and soon will read from its input stream. The kernel will generate software interrupts to coordinate

2002-562: Is remote direct memory access , which enables each CPU to access memory belonging to other CPUs. Multicomputer operating systems often support remote procedure calls where a CPU can call a procedure on another CPU, or distributed shared memory , in which the operating system uses virtualization to generate shared memory that does not physically exist. A distributed system is a group of distinct, networked computers—each of which might have their own operating system and file system. Unlike multicomputers, they may be dispersed anywhere in

2079-481: Is a C / C++ interpreter that can be embedded in LabVIEW for scripting. DSP Robotics' FlowStone DSP also uses a form of graphical programming similar to LabVIEW but is limited to the robotics industry. LabVIEW has a direct node with modeFRONTIER , a multidisciplinary and multi-objective optimization and design environment, written to allow coupling to almost any computer-aided engineering tool. Both can be part of

2156-484: Is a change away from the currently running process. Similarly, both hardware and software interrupts execute an interrupt service routine . Software interrupts may be normally occurring events. It is expected that a time slice will occur, so the kernel will have to perform a context switch . A computer program may set a timer to go off after a few seconds in case too much data causes an algorithm to take too long. Software interrupts may be error conditions, such as

2233-462: Is controlled by the run-time engine, which contains some pre-compiled code to perform common tasks defined in the "G" language. The run-time engine manages execution flow, and provides a consistent interface to supported operating systems, graphic systems and hardware components. The use of a portable run-time environment makes the source code files portable across supported platforms. LabVIEW programs are slower than equivalent compiled C code, although it

2310-422: Is difficult to define, but has been called "the layer of software that manages a computer's resources for its users and their applications ". Operating systems include the software that is always running, called a kernel —but can include other software as well. The two other types of programs that can run on a computer are system programs —which are associated with the operating system, but may not be part of

2387-516: Is not managed or standardized by any third-party standards committee. Since the "G" language is non-textual, common software tools such as versioning, side-by-side (or diff) comparison, and version code change tracking cannot be applied in the same manner as for textual programming languages. There are, however, some source code control (versioning) tools that do enable code comparison and merging, such as subversion, CVS and Perforce. In 2005, starting with LabVIEW 8.0, major versions are released around

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2464-571: Is often possible to mitigate speed issues with program optimizations. LabVIEW includes a large number of libraries containing functions for data acquisition, signal generation, mathematics, statistics, signal conditioning, analysis, integration, filtering, and other specialized abilities such as data capture from hardware sensors. In addition, it includes MathScript , a text-based programming component with built-in functions for signal processing, analysis, and mathematics. MathScript can be integrated with graphical programming using script nodes and uses

2541-443: Is only a single application running, at least conceptually, so there is no need to prevent interference between applications) and OS services are accessed via simple library calls (potentially inlining them based on compiler thresholds), without the usual overhead of context switches , in a way similarly to embedded and real-time OSes. Note that this overhead is not negligible: to the direct cost of mode switching it's necessary to add

2618-499: Is supported by most UNIX systems. MINIX was a stripped-down version of UNIX, developed in 1987 for educational uses, that inspired the commercially available, free software Linux . Since 2008, MINIX is used in controllers of most Intel microchips , while Linux is widespread in data centers and Android smartphones. The invention of large scale integration enabled the production of personal computers (initially called microcomputers ) from around 1980. For around five years,

2695-473: Is that they do not load user-installed software. Consequently, they do not need protection between different applications, enabling simpler designs. Very small operating systems might run in less than 10 kilobytes , and the smallest are for smart cards . Examples include Embedded Linux , QNX , VxWorks , and the extra-small systems RIOT and TinyOS . A real-time operating system is an operating system that guarantees to process events or data by or at

2772-435: Is the part of the operating system that provides protection between different applications and users. This protection is key to improving reliability by keeping errors isolated to one program, as well as security by limiting the power of malicious software and protecting private data, and ensuring that one program cannot monopolize the computer's resources. Most operating systems have two modes of operation: in user mode ,

2849-579: Is very similar in purpose to Ruby's RubyGems and Perl's CPAN , although it provides a graphical user interface similar to the Synaptic Package Manager . VI Package Manager provides access to a repository of the OpenG (and other) libraries for LabVIEW. Tools exist to convert MathML into "G" code. National Instruments also offers Measurement Studio , a product that offers many of the test, measurement, and control abilities of LabVIEW as

2926-542: The CP/M (Control Program for Microcomputers) was the most popular operating system for microcomputers. Later, IBM bought the DOS (Disk Operating System) from Microsoft . After modifications requested by IBM, the resulting system was called MS-DOS (MicroSoft Disk Operating System) and was widely used on IBM microcomputers. Later versions increased their sophistication, in part by borrowing features from UNIX. Apple 's Macintosh

3003-464: The CompactDAQ and CompactRIO hardware platforms and Measurement and Automation eXplorer (MAX) and Virtual Instrument Software Architecture (VISA) toolsets. LabVIEW includes a compiler that translates "G" code into native code for supported CPU platforms. The graphical code is converted into Dataflow Intermediate Representation, and then translated into chunks of executable machine code by

3080-504: The INT assembly language instruction is available. The syntax is INT X , where X is the offset number (in hexadecimal format) to the interrupt vector table . To generate software interrupts in Unix-like operating systems, the kill(pid,signum) system call will send a signal to another process. pid is the process identifier of the receiving process. signum is

3157-536: The Measurement and Automation eXplorer (MAX) LabVIEW component. In LabVIEW, virtual instruments can be configured and simulated, in order to test data processing when physical hardware is not available. The Virtual Instrument Software Architecture (VISA) is the back-end component that manages communication between LabVIEW and CompactDAQ hardware. NI SignalExpress LE is provided with every chassis controller for basic data logging and analysis. NI SignalExpress

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3234-498: The personal computer market, as of September 2024 , Microsoft Windows holds a dominant market share of around 73%. macOS by Apple Inc. is in second place (15%), Linux is in third place (5%), and ChromeOS is in fourth place (2%). In the mobile sector (including smartphones and tablets ), as of September 2023 , Android's share is 68.92%, followed by Apple's iOS and iPadOS with 30.42%, and other operating systems with .66%. Linux distributions are dominant in

3311-420: The transistor in the mid-1950s, mainframes began to be built. These still needed professional operators who manually do what a modern operating system would do, such as scheduling programs to run, but mainframes still had rudimentary operating systems such as Fortran Monitor System (FMS) and IBSYS . In the 1960s, IBM introduced the first series of intercompatible computers ( System/360 ). All of them ran

3388-410: The CPU for every byte or word transferred, and having the CPU transfer the byte or word between the device and memory, would require too much CPU time. Data is, instead, transferred between the device and memory independently of the CPU by hardware such as a channel or a direct memory access controller; an interrupt is delivered only when all the data is transferred. If a computer program executes

3465-474: The CPU to re-enter supervisor mode , placing the kernel in charge. This is called a segmentation violation or Seg-V for short, and since it is both difficult to assign a meaningful result to such an operation, and because it is usually a sign of a misbehaving program, the kernel generally resorts to terminating the offending program, and reports the error. Windows versions 3.1 through ME had some level of memory protection, but programs could easily circumvent

3542-488: The NI PXI Platform. CompactDAQ systems are managed by a chassis controller module, which controls data transfer between up-to 8 I/O modules and a PC . The chassis controller contains a timing controller that synchronizes data acquisition from all connected I/O modules. The following types of chassis controllers are available: CompactDAQ systems connect to sensors via wired or wireless I/O modules, connected to

3619-408: The VI within the back panel of upstream (calling) VIs and downstream (called) VIs to which it might be connected. There are two ways to run a VI. It can be run by itself as a program, with the front panel serving as a user interface. Alternatively, it can be treated as a node that is dropped onto the block diagram of another VI and wired to its nodes through the connector panel. In that case it runs as

3696-416: The ability to build stand-alone applications. Furthermore, it is possible to create distributed applications that communicate using a simple client–server model which takes advantage of the inherently parallel nature of "G". Applications in LabVIEW are typically designed using well-known architectures known as design patterns . The most common design patterns for graphical LabVIEW applications are listed in

3773-538: The application program, which then interacts with the user and with hardware devices. However, in some systems an application can request that the operating system execute another application within the same process, either as a subroutine or in a separate thread, e.g., the LINK and ATTACH facilities of OS/360 and successors . An interrupt (also known as an abort , exception , fault , signal , or trap ) provides an efficient way for most operating systems to react to

3850-487: The case for multiple nodes simultaneously, LabVIEW can conceptually execute in parallel. Multi-processing and multi-threading hardware is exploited automatically by the built-in scheduler, which multiplexes multiple OS threads over the nodes ready for execution. LabVIEW integrates the creation of user interfaces (termed front panels) into the program development cycle. LabVIEW programs are collections of one or more virtual instruments (VIs). Each VI has three components,

3927-453: The computer's memory. Various methods of memory protection exist, including memory segmentation and paging . All methods require some level of hardware support (such as the 80286 MMU), which does not exist in all computers. In both segmentation and paging, certain protected mode registers specify to the CPU what memory address it should allow a running program to access. Attempts to access other addresses trigger an interrupt, which causes

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4004-441: The creation of small applications. As with all introductory programming guides, the ease of construction of working "G" programs may cause the programmer to underestimate the expertise needed for high-quality "G" programming. For complex algorithms or large-scale code, a programmer must possess extensive knowledge of the special LabVIEW syntax and the topology of its memory management. The most advanced LabVIEW development systems offer

4081-471: The details of how interrupt service routines behave vary from operating system to operating system. However, several interrupt functions are common. The architecture and operating system must: A software interrupt is a message to a process that an event has occurred. This contrasts with a hardware interrupt — which is a message to the central processing unit (CPU) that an event has occurred. Software interrupts are similar to hardware interrupts — there

4158-422: The environment. Interrupts cause the central processing unit (CPU) to have a control flow change away from the currently running program to an interrupt handler , also known as an interrupt service routine (ISR). An interrupt service routine may cause the central processing unit (CPU) to have a context switch . The details of how a computer processes an interrupt vary from architecture to architecture, and

4235-512: The first week of August, to coincide with the annual National Instruments conference NI Week, and followed by a bug-fix release the following February. In 2009, National Instruments began naming releases after the year in which they are released. A bug-fix is termed a Service Pack, for example, the 2009 service pack 1 was released in February 2010. In 2017, National Instruments moved the annual conference to May and released LabVIEW 2017 alongside

4312-510: The free for non-commercial use LabVIEW and LabVIEW NXG Community editions on April 28, 2020. The programming paradigm used in the LabVIEW "G" language is based on data availability. If there is enough data available to a function, it will execute. The execution flow is determined by the structure of a graphical block diagram (the LabVIEW-source code) on which the programmer places nodes and connects them by drawing wires . A node can be

4389-416: The graphical source code. All of the objects placed on the front panel will appear in the back panel block diagram as terminals. The block diagram also contains structures and functions, chosen from a Functions palette, which perform operations on controls and supply data to indicators. The connector panel has terminals whose wires go to or come from nodes in the front and back panels, and is used to represent

4466-410: The hardware checks that the software is only executing legal instructions, whereas the kernel has unrestricted powers and is not subject to these checks. The kernel also manages memory for other processes and controls access to input/output devices. The operating system provides an interface between an application program and the computer hardware, so that an application program can interact with

4543-493: The hardware only by obeying rules and procedures programmed into the operating system. The operating system is also a set of services which simplify development and execution of application programs. Executing an application program typically involves the creation of a process by the operating system kernel , which assigns memory space and other resources, establishes a priority for the process in multi-tasking systems, loads program binary code into memory, and initiates execution of

4620-418: The indirect pollution of important processor structures (like CPU caches , the instruction pipeline , and so on) which affects both user-mode and kernel-mode performance. The first computers in the late 1940s and 1950s were directly programmed either with plugboards or with machine code inputted on media such as punch cards , without programming languages or operating systems. After the introduction of

4697-404: The interrupt request, the operating system will: When the writing process has its time slice expired, the operating system will: With the program counter now reset, the interrupted process will resume its time slice. Among other things, a multiprogramming operating system kernel must be responsible for managing all system memory which is currently in use by the programs. This ensures that

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4774-431: The kernel—and applications—all other software. There are three main purposes that an operating system fulfills: With multiprocessors multiple CPUs share memory. A multicomputer or cluster computer has multiple CPUs, each of which has its own memory . Multicomputers were developed because large multiprocessors are difficult to engineer and prohibitively expensive; they are universal in cloud computing because of

4851-470: The longevity and popularity of the LabVIEW platform and the ability for users to extend its functions, a large ecosystem of third-party add-ons has developed via contributions from the community. Most of these add-ons are available for direct download and installation into LabVIEW using the VI Package Manager (VIPM), the official package manager for LabVIEW add-ons. National Instruments also hosts

4928-400: The memory allocated to a different one. Around the same time, teleprinters began to be used as terminals so multiple users could access the computer simultaneously. The operating system MULTICS was intended to allow hundreds of users to access a large computer. Despite its limited adoption, it can be considered the precursor to cloud computing . The UNIX operating system originated as

5005-408: The need to use it. A general protection fault would be produced, indicating a segmentation violation had occurred; however, the system would often crash anyway. The use of virtual memory addressing (such as paging or segmentation) means that the kernel can choose what memory each program may use at any given time, allowing the operating system to use the same memory locations for multiple tasks. If

5082-408: The open-source Android operating system (introduced 2008), with a Linux kernel and a C library ( Bionic ) partially based on BSD code, became most popular. The components of an operating system are designed to ensure that various parts of a computer function cohesively. With the de facto obsoletion of DOS , all user software must interact with the operating system to access hardware. The kernel

5159-420: The operating system acts as an intermediary between programs and the computer hardware, although the application code is usually executed directly by the hardware and frequently makes system calls to an OS function or is interrupted by it. Operating systems are found on many devices that contain a computer – from cellular phones and video game consoles to web servers and supercomputers . In

5236-421: The piping. Signals may be classified into 7 categories. The categories are: Input/output (I/O) devices are slower than the CPU. Therefore, it would slow down the computer if the CPU had to wait for each I/O to finish. Instead, a computer may implement interrupts for I/O completion, avoiding the need for polling or busy waiting. Some computers require an interrupt for each character or word, costing

5313-499: The programmer or the user with the perception that there is a much larger amount of RAM in the computer than is really there. CompactDAQ CompactDAQ is a data acquisition platform built by National Instruments that includes a broad set of compatible hardware and software. CompactDAQ integrates hardware for data I/O with LabVIEW software to enable engineers to collect, process and analyse sensor data. CompactDAQ systems are less expensive than equivalent systems within

5390-418: The same operating system— OS/360 —which consisted of millions of lines of assembly language that had thousands of bugs . The OS/360 also was the first popular operating system to support multiprogramming , such that the CPU could be put to use on one job while another was waiting on input/output (I/O). Holding multiple jobs in memory necessitated memory partitioning and safeguards against one job accessing

5467-615: The same process workflow description and can be virtually driven by the optimization technologies available in modeFRONTIER. Operating system An operating system ( OS ) is system software that manages computer hardware and software resources, and provides common services for computer programs . Time-sharing operating systems schedule tasks for efficient use of the system and may also include accounting software for cost allocation of processor time , mass storage , peripherals, and other resources. For hardware functions such as input and output and memory allocation ,

5544-619: The server and supercomputing sectors. Other specialized classes of operating systems (special-purpose operating systems), such as embedded and real-time systems, exist for many applications. Security-focused operating systems also exist. Some operating systems have low system requirements (e.g. light-weight Linux distribution ). Others may have higher system requirements. Some operating systems require installation or may come pre-installed with purchased computers ( OEM -installation), whereas others may run directly from media (i.e. live CD ) or flash memory (i.e. USB stick). An operating system

5621-400: The signal number (in mnemonic format) to be sent. (The abrasive name of kill was chosen because early implementations only terminated the process.) In Unix-like operating systems, signals inform processes of the occurrence of asynchronous events. To communicate asynchronously, interrupts are required. One reason a process needs to asynchronously communicate to another process solves

5698-400: The size of the machine needed. The different CPUs often need to send and receive messages to each other; to ensure good performance, the operating systems for these machines need to minimize this copying of packets . Newer systems are often multiqueue —separating groups of users into separate queues —to reduce the need for packet copying and support more concurrent users. Another technique

5775-557: The table below. complex logic, communication protocols LabVIEW includes extensive support for interfacing to instruments, cameras, and other devices. Users interface to hardware by either writing direct bus commands (USB, GPIB, Serial) or using high-level, device-specific drivers that provide native "G" function nodes for controlling the device. National Instruments makes thousands of device drivers available for download on their Instrument Driver Network (IDNet). LabVIEW has built-in support for other National Instruments products, such as

5852-473: The world. Middleware , an additional software layer between the operating system and applications, is often used to improve consistency. Although it functions similarly to an operating system, it is not a true operating system. Embedded operating systems are designed to be used in embedded computer systems , whether they are internet of things objects or not connected to a network. Embedded systems include many household appliances. The distinguishing factor

5929-406: Was the first popular computer to use a graphical user interface (GUI). The GUI proved much more user friendly than the text-only command-line interface earlier operating systems had used. Following the success of Macintosh, MS-DOS was updated with a GUI overlay called Windows . Windows later was rewritten as a stand-alone operating system, borrowing so many features from another ( VAX VMS ) that

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