Control-V
Encyclopedia
In computing
, Control-V is a control character
in ASCII code, also known as the synchronous idle (SYN
) character. It is generated by pressing the key while holding down the key on a computer keyboard
. The equivalent Mac OS
key combination on Apple computers is Command
-V.
In many GUI
environments, including Microsoft Windows
and most desktop environment
s based on the X Window System
, and in applications such as word processing
software running in those environments, control-V can be used to paste text or other content (if supported) from the clipboard
at the current cursor
position. Control-V was one of a handful of keyboard
sequences chosen by the program designers at Xerox PARC
to control text editing
. Presumably these particular keystrokes were chosen because of their location on a standard QWERTY keyboard, since the Z
(undo), X
(cut), C
(copy), and V (paste) keys are located together at the left end of the bottom row of the standard QWERTY
keyboard.
IBM Input/output
devices utilizing the bisync link protocol use the SYN character code to signal the beginning of each data frame transmitted.
Unix
interactive terminals use Control-V to mean "the next character should be treated literally" (the mnemonic here is "v is for verbatim"). This allows a user to insert a literal Control-C or Control-H or similar control characters that would otherwise be handled by the terminal. This behavior was copied by text editors like vi
and Unix shells
like bash and tcsh
, which offer text editing on the command line.
Computing
Computing is usually defined as the activity of using and improving computer hardware and software. It is the computer-specific part of information technology...
, Control-V is a control character
Control character
In computing and telecommunication, a control character or non-printing character is a code point in a character set, that does not in itself represent a written symbol.It is in-band signaling in the context of character encoding....
in ASCII code, also known as the synchronous idle (SYN
Synchronous idle
Synchronous Idle is the ASCII control character 22 , represented as ^V in caret notation. Synchronous Idle is used in some synchronous serial communication systems such as Teletype machines or the bisync protocol to provide a signal from which synchronous correction may be achieved between data...
) character. It is generated by pressing the key while holding down the key on a computer keyboard
Computer keyboard
In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...
. The equivalent Mac OS
Mac OS
Mac OS is a series of graphical user interface-based operating systems developed by Apple Inc. for their Macintosh line of computer systems. The Macintosh user experience is credited with popularizing the graphical user interface...
key combination on Apple computers is Command
Command key
The Command key, also historically known as the Apple key, open-Apple key or meta key is a modifier key present on Apple Keyboards. The Command key's purpose is to allow the user to enter keyboard shortcut commands to GUI applications...
-V.
In many GUI
Graphical user interface
In computing, a graphical user interface is a type of user interface that allows users to interact with electronic devices with images rather than text commands. GUIs can be used in computers, hand-held devices such as MP3 players, portable media players or gaming devices, household appliances and...
environments, including Microsoft Windows
Microsoft Windows
Microsoft Windows is a series of operating systems produced by Microsoft.Microsoft introduced an operating environment named Windows on November 20, 1985 as an add-on to MS-DOS in response to the growing interest in graphical user interfaces . Microsoft Windows came to dominate the world's personal...
and most desktop environment
Desktop environment
In graphical computing, a desktop environment commonly refers to a style of graphical user interface derived from the desktop metaphor that is seen on most modern personal computers. These GUIs help the user in easily accessing, configuring, and modifying many important and frequently accessed...
s based on the X Window System
X Window System
The X window system is a computer software system and network protocol that provides a basis for graphical user interfaces and rich input device capability for networked computers...
, and in applications such as word processing
Word processor
A word processor is a computer application used for the production of any sort of printable material....
software running in those environments, control-V can be used to paste text or other content (if supported) from the clipboard
Clipboard (software)
The clipboard is a software facility that can be used for short-term data storage and/or data transfer between documents or applications, via copy and paste operations...
at the current cursor
Cursor (computers)
In computing, a cursor is an indicator used to show the position on a computer monitor or other display device that will respond to input from a text input or pointing device. The flashing text cursor may be referred to as a caret in some cases...
position. Control-V was one of a handful of keyboard
Computer keyboard
In computing, a keyboard is a typewriter-style keyboard, which uses an arrangement of buttons or keys, to act as mechanical levers or electronic switches...
sequences chosen by the program designers at Xerox PARC
Xerox PARC
PARC , formerly Xerox PARC, is a research and co-development company in Palo Alto, California, with a distinguished reputation for its contributions to information technology and hardware systems....
to control text editing
Text editor
A text editor is a type of program used for editing plain text files.Text editors are often provided with operating systems or software development packages, and can be used to change configuration files and programming language source code....
. Presumably these particular keystrokes were chosen because of their location on a standard QWERTY keyboard, since the Z
Control-Z
In computing, is a control character in ASCII code, also known as the substitute character or a keyboard shortcut. Strictly speaking, is not a printable character at all but a code for control purposes, though it is sometimes rendered by two characters as ^Z. It is generated by pressing the key...
(undo), X
Control-X
In computing, control-X is a control character in ASCII code, also known as the cancel character. It is generated by pressing the key while holding down the key on a computer keyboard...
(cut), C
Control-C
Control-C is a common computer command. It is generated by pressing the key while holding down the key on a computer keyboard.In graphical user interface environments that use the control key to control the active program, control-C is often used to copy highlighted text to the clipboard...
(copy), and V (paste) keys are located together at the left end of the bottom row of the standard QWERTY
QWERTY
QWERTY is the most common modern-day keyboard layout. The name comes from the first six letters appearing in the topleft letter row of the keyboard, read left to right: Q-W-E-R-T-Y. The QWERTY design is based on a layout created for the Sholes and Glidden typewriter and sold to Remington in the...
keyboard.
IBM Input/output
Input/output
In computing, input/output, or I/O, refers to the communication between an information processing system , and the outside world, possibly a human, or another information processing system. Inputs are the signals or data received by the system, and outputs are the signals or data sent from it...
devices utilizing the bisync link protocol use the SYN character code to signal the beginning of each data frame transmitted.
Unix
Unix
Unix is a multitasking, multi-user computer operating system originally developed in 1969 by a group of AT&T employees at Bell Labs, including Ken Thompson, Dennis Ritchie, Brian Kernighan, Douglas McIlroy, and Joe Ossanna...
interactive terminals use Control-V to mean "the next character should be treated literally" (the mnemonic here is "v is for verbatim"). This allows a user to insert a literal Control-C or Control-H or similar control characters that would otherwise be handled by the terminal. This behavior was copied by text editors like vi
Vi
vi is a screen-oriented text editor originally created for the Unix operating system. The portable subset of the behavior of vi and programs based on it, and the ex editor language supported within these programs, is described by the Single Unix Specification and POSIX.The original code for vi...
and Unix shells
Shell (computing)
A shell is a piece of software that provides an interface for users of an operating system which provides access to the services of a kernel. However, the term is also applied very loosely to applications and may include any software that is "built around" a particular component, such as web...
like bash and tcsh
Tcsh
tcsh is a Unix shell based on and compatible with the C shell . It is essentially the C shell with programmable command line completion, command-line editing, and a few other features.-History:...
, which offer text editing on the command line.
Representation
- ASCIIASCIIThe American Standard Code for Information Interchange is a character-encoding scheme based on the ordering of the English alphabet. ASCII codes represent text in computers, communications equipment, and other devices that use text...
and UnicodeUnicodeUnicode is a computing industry standard for the consistent encoding, representation and handling of text expressed in most of the world's writing systems...
representation of "Synchronous Idle":- Octal code: 26
- Decimal code: 22
- Hexadecimal code: 16, U+0016
- Mnemonic symbol: SYNSynchronous idleSynchronous Idle is the ASCII control character 22 , represented as ^V in caret notation. Synchronous Idle is used in some synchronous serial communication systems such as Teletype machines or the bisync protocol to provide a signal from which synchronous correction may be achieved between data...