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Fully Qualified Name
In computer programming, a fully qualified name is an unambiguous name that specifies which object, function, or variable a call refers to without regard to the context of the call. In a hierarchical structure, a name is fully qualified when it "is complete in the sense that it includes (a) all names in the hierarchic sequence above the given element and (b) the name of the given element itself." Programming Fully qualified names explicitly refer to namespaces that would otherwise be implicit because of the scope of the call. While always done to eliminate ambiguity, this can mean different things dependent on context. Commonly encountered applications of the notion have been given their own names, such as the fully qualified domain name and the fully qualified file name. Examples To distinguish a fully qualified name from a regular name, C++, Tcl, Perl and Ruby use two colons (::), and Java uses dots (.), as does Visual Basic .NET. and C#. In Java, ActionScript, and ot ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Programming
Computer programming is the process of performing a particular computation (or more generally, accomplishing a specific computing result), usually by designing and building an executable computer program. Programming involves tasks such as analysis, generating algorithms, profiling algorithms' accuracy and resource consumption, and the implementation of algorithms (usually in a chosen programming language, commonly referred to as coding). The source code of a program is written in one or more languages that are intelligible to programmers, rather than machine code, which is directly executed by the central processing unit. The purpose of programming is to find a sequence of instructions that will automate the performance of a task (which can be as complex as an operating system) on a computer, often for solving a given problem. Proficient programming thus usually requires expertise in several different subjects, including knowledge of the application domain, specialized algorit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scalar (computing)
Scalar processors are a class of computer processors that process only one data item at a time. Typical data items include integers and floating point numbers. Classification A scalar processor is classified as a single instruction, single data (SISD) processor in Flynn's taxonomy. The Intel 486 is an example of a scalar processor. It is to be contrasted with a vector processor where a single instruction operates simultaneously on multiple data items (and thus is referred to as a single instruction, multiple data (SIMD) processor). The difference is analogous to the difference between scalar and vector arithmetic. The term ''scalar'' in computing dates to the 1970 and 1980s when vector processors were first introduced. It was originally used to distinguish the older designs from the new vector processors. Superscalar processor A superscalar processor (such as the Intel P5) may execute more than one instruction during a clock cycle by simultaneously dispatching multiple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UNIVAC Series 90
The Univac 90/60 system front panel The Univac Series 90 is an obsolete family of mainframe class computer systems from UNIVAC first introduced in 1973. The low end family members included the 90/25, 90/30 and 90/40 that ran the OS/3 operating system. The intermediate members of the family were the 90/60 and 90/70, while the 90/80, announced in 1976, was the high end system. The 90/60 through 90/80 systems all ran the Univac’s virtual memory operating system, VS/9. The Series 90 systems were the replacement for the UNIVAC 9000 series of low end, mainframe systems marketed by Sperry Univac during the 1960s. The 9000 series systems were byte-addressable machines with an instruction set that was compatible with the IBM System/360. The family included the 9200, 9300, 9400, and 9480 systems. The 9200 and 9300 ran the ''Minimum Operating system''. This system was loaded from cards, but thereafter also supported magnetic tape or magnetic disk for programs and data. The 9400 a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PDP-11
The PDP-11 is a series of 16-bit minicomputers sold by Digital Equipment Corporation (DEC) from 1970 into the 1990s, one of a set of products in the Programmed Data Processor (PDP) series. In total, around 600,000 PDP-11s of all models were sold, making it one of DEC's most successful product lines. The PDP-11 is considered by some experts to be the most popular minicomputer. The PDP-11 included a number of innovative features in its instruction set and additional general-purpose registers that made it much easier to program than earlier models in the PDP series. Further, the innovative Unibus system allowed external devices to be easily interfaced to the system using direct memory access, opening the system to a wide variety of peripherals. The PDP-11 replaced the PDP-8 in many real-time computing applications, although both product lines lived in parallel for more than 10 years. The ease of programming of the PDP-11 made it very popular for general-purpose computing uses a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
RSTS/E
RSTS () is a multi-user time-sharing operating system developed by Digital Equipment Corporation (DEC, now part of Hewlett-Packard) for the PDP-11 series of 16-bit minicomputers. The first version of RSTS (RSTS-11, Version 1) was implemented in 1970 by DEC software engineers that developed the TSS-8 time-sharing operating system for the PDP-8. The last version of RSTS (RSTS/E, Version 10.1) was released in September 1992. RSTS-11 and RSTS/E are usually referred to just as "RSTS" and this article will generally use the shorter form. RSTS-11 supports the BASIC programming language, an extended version called BASIC-PLUS, developed under contract by ''Evans Griffiths & Hart'' of Boston,. Starting with RSTS/E version 5B, DEC added support for additional programming languages by emulating the execution environment of the RT-11 and RSX-11 operating systems. Acronyms and abbreviations *BTSS (Basic Time Sharing System – never marketed) – The first name for RSTS. *CCL (Concise Comm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
MUSIC/SP
''MUSIC/SP (Multi-User System for Interactive Computing/System Product''; originally "McGill University System for Interactive Computing") was developed at McGill University in the 1970s from an early IBM time-sharing system called RAX ( Remote Access Computing System). The system ran on IBM S/360, S/370, and 4300-series mainframe hardware, and offered then-novel features such as file access control and data compression. It was designed to allow academics and students to create and run their programs interactively on terminals, in an era when most mainframe computing was still being done from punched cards. Over the years, development continued and the system evolved to embrace email, the Internet and eventually the World Wide Web. At its peak in the late 1980s, there were over 250 universities, colleges and high school districts that used the system in North and South America, Europe and Asia. By the time of its demise, the ''MUSIC'' time-sharing software had been adap ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mainframe Computer
A mainframe computer, informally called a mainframe or big iron, is a computer used primarily by large organizations for critical applications like bulk data processing for tasks such as censuses, industry and consumer statistics, enterprise resource planning, and large-scale transaction processing. A mainframe computer is large but not as large as a supercomputer and has more processing power than some other classes of computers, such as minicomputers, servers, workstations, and personal computers. Most large-scale computer-system architectures were established in the 1960s, but they continue to evolve. Mainframe computers are often used as servers. The term ''mainframe'' was derived from the large cabinet, called a ''main frame'', that housed the central processing unit and main memory of early computers. Later, the term ''mainframe'' was used to distinguish high-end commercial computers from less powerful machines. Design Modern mainframe design is characterized less by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Path (computing)
A path is a string of characters used to uniquely identify a location in a directory structure. It is composed by following the directory tree hierarchy in which components, separated by a delimiting character, represent each directory. The delimiting character is most commonly the slash ("/"), the backslash character ("\"), or colon (":"), though some operating systems may use a different delimiter. Paths are used extensively in computer science to represent the directory/file relationships common in modern operating systems and are essential in the construction of Uniform Resource Locators (URLs). Resources can be represented by either ''absolute'' or ''relative'' paths. History Multics first introduced a hierarchical file system with directories (separated by ">") in the mid-1960s. Around 1970, Unix introduced the slash character ("/") as its directory separator. In 1981, the first version of Microsoft DOS was released. MS-DOS 1.0 did not support file directories. Als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Drive Letter Assignment
In computer data storage, drive letter assignment is the process of assigning alphabetical identifiers to volumes. Unlike the concept of UNIX mount points, where volumes are named and located arbitrarily in a single hierarchical namespace, drive letter assignment allows multiple highest-level namespaces. Drive letter assignment is thus a process of using letters to name the roots of the "forest" representing the file system; each volume holds an independent "tree" (or, for non-hierarchical file systems, an independent list of files). Origin The concept of drive letters, as used today, presumably owes its origins to IBM's VM family of operating systems, dating back to CP/CMS in 1967 (and its research predecessor CP-40), by way of Digital Research's (DRI) CP/M. The concept evolved through several steps: * CP/CMS uses drive letters to identify '' minidisks'' attached to a user session. A full file reference (''pathname'' in today's parlance) consists of a ''filename'', a '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Root Directory
In a computer file system, and primarily used in the Unix and Unix-like operating systems, the root directory is the first or top-most directory in a hierarchy. It can be likened to the trunk of a tree, as the starting point where all branches originate from. The root file system is the file system contained on the same disk partition on which the root directory is located; it is the filesystem on top of which all other file systems are mounted as the system boots up. Unix-like systems Unix abstracts the nature of this tree hierarchy entirely and in Unix and Unix-like systems the root directory is denoted by the / (slash) sign. Though the root directory is conventionally referred to as /, the directory entry itself has no name its path is the "empty" part before the initial directory separator character (/). All file system entries, including mounted file systems are "branches" of this root. chroot In UNIX-like operating systems, each process has its own idea of what the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Current Directory
In computing, the working directory of a process is a directory of a hierarchical file system, if any, dynamically associated with each process. It is sometimes called the current working directory (CWD), e.g. the BSD getcwd function, or just current directory. When the process refers to a file using a simple file name or relative path (as opposed to a file designated by a full path from a root directory), the reference is interpreted relative to the working directory of the process. So for example a process with working directory /rabbit-shoes that asks to create the file foo.txt will end up creating the file /rabbit-shoes/foo.txt. In operating systems In most computer file systems, every directory has an entry (usually named ".") which points to the directory itself. In most DOS and UNIX command shells, as well as in the Microsoft Windows command line interpreters cmd.exe and Windows PowerShell, the working directory can be changed by using the CD or CHDIR commands. In Un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microsoft Windows
Windows is a group of several Proprietary software, proprietary graphical user interface, graphical operating system families developed and marketed by Microsoft. Each family caters to a certain sector of the computing industry. For example, Windows NT for consumers, Windows Server for servers, and Windows IoT for embedded systems. Defunct Windows families include Windows 9x, Windows Mobile, and Windows Phone. The first version of Windows was released on November 20, 1985, as a graphical operating system shell for MS-DOS in response to the growing interest in graphical user interfaces (GUIs). Windows is the most popular desktop operating system in the world, with Usage share of operating systems, 75% market share , according to StatCounter. However, Windows is not the most used operating system when including both mobile and desktop OSes, due to Android (operating system), Android's massive growth. , the most recent version of Windows is Windows 11 for consumer Personal compu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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