|
Chain Loading
Chain loading is a method used by computer programs to replace the currently executing program with a new program, using a common data area to pass information from the current program to the new program. It occurs in several areas of computing. Chain loading is similar to the use of overlays. Unlike overlays, however, chain loading replaces the currently executing program in its entirety. Overlays usually replace only a portion of the running program. Like the use of overlays, the use of chain loading increases the I/O load of an application. Chain loading in boot manager programs In operating system boot manager programs, chain loading is used to pass control from the boot manager to a boot sector. The target boot sector is loaded in from disk, replacing the in-memory boot sector from which the boot manager itself was bootstrapped, and executed. Chain loading in Unix In Unix (and in Unix-like operating systems), the exec() system call is used to perform chain loading ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Program
A computer program is a sequence or set of instructions in a programming language for a computer to execute. Computer programs are one component of software, which also includes documentation and other intangible components. A computer program in its human-readable form is called source code. Source code needs another computer program to execute because computers can only execute their native machine instructions. Therefore, source code may be translated to machine instructions using the language's compiler. ( Assembly language programs are translated using an assembler.) The resulting file is called an executable. Alternatively, source code may execute within the language's interpreter. If the executable is requested for execution, then the operating system loads it into memory and starts a process. The central processing unit will soon switch to this process so it can fetch, decode, and then execute each machine instruction. If the source code is requested for execution, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kernel (operating System)
The kernel is a computer program at the core of a computer's operating system and generally has complete control over everything in the system. It is the portion of the operating system code that is always resident in memory and facilitates interactions between hardware and software components. A full kernel controls all hardware resources (e.g. I/O, memory, cryptography) via device drivers, arbitrates conflicts between processes concerning such resources, and optimizes the utilization of common resources e.g. CPU & cache usage, file systems, and network sockets. On most systems, the kernel is one of the first programs loaded on startup (after the bootloader). It handles the rest of startup as well as memory, peripherals, and input/output (I/O) requests from software, translating them into data-processing instructions for the central processing unit. The critical code of the kernel is usually loaded into a separate area of memory, which is protected from access by application ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Art Of Unix Programming
''The Art of Unix Programming'' by Eric S. Raymond is a book about the history and culture of Unix programming from its earliest days in 1969 to 2003 when it was published, covering both genetic derivations such as BSD and conceptual ones such as Linux. The author utilizes a comparative approach to explaining Unix by contrasting it to other operating systems including desktop-oriented ones such as Microsoft Windows and the classic Mac OS to ones with research roots such as EROS and Plan 9 from Bell Labs. The book was published by Addison-Wesley, September 17, 2003, and is also available online, under a Creative Commons license with additional clauses. Contributors The book contains many contributions, quotations and comments from UNIX gurus past and present. These include: *Ken Arnold (author of curses and co-author of '' Rogue'') *Steve Bellovin *Stuart Feldman *Jim Gettys *Stephen C. Johnson *Brian Kernighan * David Korn *Mike Lesk *Doug McIlroy *Marshall Kirk McKusick *Keit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU GRUB
GNU GRUB (short for GNU GRand Unified Bootloader, commonly referred to as GRUB) is a boot loader package from the GNU Project. GRUB is the reference implementation of the Free Software Foundation's Multiboot Specification, which provides a user the choice to boot one of multiple operating systems installed on a computer or select a specific Kernel (computer science), kernel configuration available on a particular operating system's partitions. GNU GRUB was developed from a package called the ''Grand Unified Bootloader'' (a play on Grand Unified Theory). It is predominantly used for Unix-like systems. The GNU, GNU operating system uses GNU GRUB as its boot loader, as do most Linux distributions and the Solaris (operating system), Solaris operating system on x86 systems, starting with the Solaris 10 1/06 release. Operation Booting When a computer is turned on, its BIOS finds the primary bootable device (usually the computer's hard disk) and runs the initial Bootstrapping (c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHAIN (CONFIG
{{disambig ...
CHAIN may refer to: * CHAIN (industry standard), an acronym for Ceced Home Appliances Interoperating Network, a standard for a multi-brands home network of interactive household appliances. * Controlled and Harmonised Aeronautical Information Network, a concept of EUROCONTROL to improve the quality of aeronautical data. * Canadian High Arctic Ionospheric Network, an array of ground-based radio instruments See also * Chain (other) A chain is a series of connected links which are typically made of metal. Chain may also refer to: Accessories and apparel * Chain mail, a type of armor made of interlocking chain links * Neck chain (or necklace), a type of jewelry which is wor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
OS/360 And Successors
OS/360, officially known as IBM System/360 Operating System, is a discontinued batch processing operating system developed by IBM for their then-new System/360 mainframe computer, announced in 1964; it was influenced by the earlier IBSYS/IBJOB and Input/Output Control System (IOCS) packages for the IBM 7090/7094 and even more so by the PR155 Operating System for the IBM 1410/ 7010 processors. It was one of the earliestJust a few years after Atlas Supervisor, Burroughs MCP and GECOS operating systems to require the computer hardware to include at least one direct access storage device. Although OS/360 itself was discontinued, successor operating systems, including the virtual storage MVS and the 64-bit z/OS, are still run and maintain application-level compatibility with OS/360. Overview IBM announced three different levels of OS/360, generated from the same tapes and sharing most of their code. IBM eventually renamed these options and made some significant design changes: ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
GNU Fortran
GNU Fortran or GFortran is the GNU Fortran compiler, which is part of the GNU Compiler Collection (GCC). It includes full support for the Fortran#Fortran 95, Fortran 95 language, and supports large parts of the Fortran#Fortran 2003, Fortran 2003 and Fortran#Fortran 2008, Fortran 2008 standards. It supports the OpenMP Cross-platform software, multi-platform shared memory multiprocessing, up to its latest version (4.5). GFortran is also compatible with most language extensions and compilation options supported by g77, and many other popular extensions of the Fortran language. Since GCC version 4.0.0, released in April 2005, GFortran has replaced the older g77 compiler. The new Fortran Front-end (computing), front-end for GCC was rewritten from scratch, after the principal author and maintainer of g77, Craig Burley, decided in 2001 to stop working on the g77 front end. GFortran fork (software development), forked off from g95 in January 2003, which itself started in early 2000. The two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Core Common Area
The core common area is that . Named after magnetic core memory, the term has persisted into the modern era and is commonly used by both the Fortran and BASIC languages. See also * Chain loading Chain loading is a method used by computer programs to replace the currently executing program with a new program, using a common data area to pass information from the current program to the new program. It occurs in several areas of computing. ... Operating system technology {{Compu-prog-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
BBC BASIC
BBC BASIC is a version of the BASIC programming language released in 1981 as the native programming language for the BBC Micro home/personal computer, providing a standardized language for a UK computer literacy project of the BBC. It was written mainly by Sophie Wilson. BBC BASIC, based on the older Atom BASIC for the Acorn Atom, extended contemporary microcomputer BASICs with named DEF PROC/DEF FN procedures and functions, REPEAT UNTIL loops, and IF THEN ELSE structures inspired by COMAL. The interpreter also included statements for controlling the BBC Micro's four-channel sound output and its low-/high-resolution eight-mode graphics display. Due to a number of optimizations, BBC BASIC ran programs much faster than Microsoft BASIC running on similar machines. The optimizations included using multiple linked lists for variable lookup rather than a single long list, pre-defining the location of integer variables, and having separate integer maths routines. Speed was furthe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Line Number
In computing, a line number is a method used to specify a particular sequence of characters in a text file. The most common method of assigning numbers to lines is to assign every line a unique number, starting at 1 for the first line, and incrementing by 1 for each successive line. In the C programming language the line number of a source code line is one greater than the number of new-line characters read or introduced up to that point. Programmers could also assign line numbers to statements in older programming languages, such as Fortran, JOSS, and BASIC. In Fortran, not every statement needed a line number, and line numbers did not have to be in sequential order. The purpose of line numbers was for branching and for reference by formatting statements. Both JOSS and BASIC made line numbers a required element of syntax. The primary reason for this is that most operating systems at the time lacked interactive text editors; since the programmer's interface was usually limit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Commodore BASIC
Commodore BASIC, also known as PET BASIC or CBM-BASIC, is the dialect of the BASIC programming language used in Commodore International's 8-bit home computer line, stretching from the PET of 1977 to the C128 of 1985. The core is based on 6502 Microsoft BASIC, and as such it shares many characteristics with other 6502 BASICs of the time, such as Applesoft BASIC. Commodore licensed BASIC from Microsoft in 1977 on a "pay once, no royalties" basis after Jack Tramiel turned down Bill Gates' offer of a per unit fee, stating, "I'm already married," and would pay no more than for a perpetual license. The original PET version was very similar to the original Microsoft implementation with few modifications. BASIC 2.0 on the C64 was also similar, and was also seen on C128s (in C64 mode) and other models. Later PETs featured BASIC 4.0, similar to the original but adding a number of commands for working with floppy disks. BASIC 3.5 was the first to really deviate, adding a number of comma ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
