Operating Arrangement Architecture Command band interfaces

 13 July 16:14   A command band interface or CLI is a adjustment of interacting with a computer by giving it curve of textual commands (that is, a arrangement of characters) either from keyboard ascribe or from a script. They were originally developed for interfacing with computers over buzzer machines in the 1950s. It is occasionally aswell referred to as a CLUE, for Command Band User Environment. Some altercate that the CLI is not infact a user interface at all, but a programming language, entered one band at a time, and has actual little account for users compared to developers. Indeed, command curve are alotof generally acclimated in accurate or engineering environments for programming.

    In its simplest form, the computer displays a prompt, the user types a command on the keyboard and terminates the command with a keyboard key (usually the Access key) and the computer executes the command. The computer then carries out the command given. The appellation is usually acclimated in adverse to a graphical user interface (GUI) in which commands are about issued by affective a arrow (via a pointing device) to a area of the awning and acute a button army on the pointing accessory (clicking).

    Programs that apparatus these interfaces are generally alleged command band interpreters. Examples of such programs cover the assorted altered Unix shells, VMS DCL (Digital Command Language), and accompanying designs like CP/M and Berth command.com, both based heavily on DECs RSX and RSTS operating arrangement interfaces (which were aswell command band interfaces). Microsoft claims their next above operating system, Windows Vista, will cover an added command band interface called MSH (Microsoft Shell, codename Monad), which combines the appearance of acceptable Unix shells with the acquisitive .NET framework.

    Some applications accommodate command curve as well. The CAD program AutoCAD is a arresting example. Addition accomplished archetype is the engineering/scientific after ciphering amalgamation Matlab, in which about no GUI exists and/or is accidental for assuming alotof of the calculations. In some accretion environments like the Oberon or Smalltalk user interface, alotof of the argument which appears on the awning may be acclimated for giving commands.

    The commands accustomed on a command band interface are generally of the form

     [doSomething] [how] [toAFile]

    or

     [doSomething] [how] < [inputFile] > [outputFile]

    doSomething corresponds to a verb, how to an adverb (it describes how the command should be performed in this instance — for example, should it be decidedly verbose, or decidedly quiet) and toAFile to an item (often one or added files) adjoin which the command should be run. The standalone > in the additional archetype is a redirection character, cogent the operating arrangement (i.e., usually a command carapace interpreter) to forward the achievement of the antecedent commands (that is, those on the larboard of >) to some additional abode (that is, the book called to the appropriate of the >). Addition accepted and important redirection appearance is the aqueduct (|), which tells the CLI to amusement the achievement of this command as the ascribe of another; this can be a actual able apparatus for the user, as explained beneath activity (Unix) and pipes and filters.

    Command band interface