Control-V

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 V key while holding down the Ctrl 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 environments 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 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.

Representation

• ASCII and Unicode representation of "Synchronous Idle":

  Octal code: 26

  Decimal code: 22

  Hexadecimal code: 16, U+0016

  Mnemonic symbol: SYN

See also

• Control-C
• Control-X
• Control-Z