![]() On terminals that use UTF-8 encoding, both forms take 2 bytes, but the two-character sequence is more clear. Only the two-character sequence is recognized by devices that support just ASCII (7-bit bytes) or devices that support 8-bit bytes but use the 0x80–0x9F control character range for other purposes. The ESC+ [ two-character sequence is more often used than the single-character alternative, for details see C0 and C1 control codes. There is a single-character CSI (155/ 0x9B/ 0233) as well. The final character of these sequences is in the range ASCII 64 to 126 to ~). This sequence is called CSI for Control Sequence Introducer (or Control Sequence Initiator). Most of the sequences are however more than two characters, and start with the characters ESC and [ (left bracket). For two character sequences the second character is in the range ASCII 64 to 95 ( to _). SetConsoleTextAttribute(ConOut, background|FOREGROUND_RED|FOREGROUND_INTENSITY) Įscape sequences start with the character ESC ( ASCII decimal 27/ hex 0x1B/ octal 033). Software can manipulate the console with ioctl-like Console API interlaced with the text output, for instance: ANSI.SYS also worked in NT-derived systems for 16-bit legacy programs executing under the NTVDM.Ĭonsole windows in all versions of Windows do not support ANSI escape sequences at all. ĪNSI.SYS and similar drivers continued to work in through Windows 98, and even in Windows Me, when they were set to native DOS mode (the characters taking the whole screen). Extreme slowness and the fact that it was not installed by default made usage by software almost non-existent software continued to directly manipulate the hardware to get the text display needed. MS-DOS 2.0 introduced the ability to add a device driver for the ANSI escape sequences – the de facto standard being ANSI.SYS, but others like ANSI.COM, and NANSI.SYS are used as well. Any display effects had to be done with BIOS calls (or far more often by directly manipulating the IBM PC hardware). Only a few control characters ( CR, LF, BS) were interpreted, making it impossible to do any kind of full-screen application. MS-DOS 1.0 did not support the ANSI or any other escape sequences. Utility programs such as tput output them, as well as in low-level programming libraries, such as termcap or terminfo, or a higher-level library such as curses. ls, grep, Vim, and Emacs) can generate them, and until 2000 or so this was the primary way they produced their display, even if that display was almost always inside a terminal emulator on a graphics display. Mefford's ANSI.COM, and Jason Hood's ansicon. Some support for text from local programs on Windows is offered through alternate command processors such as JP Software's 4NT, Michael J. Terminal programs for Microsoft Windows designed to show text from an outside source (a serial port, modem, or socket) also interpret them. ![]() The native text console in Linux (the text seen when X is not running) also interprets them. Most terminal emulators running on Unix-like systems (such as xterm and the OS X Terminal) interpret ANSI escape sequences. The popularity of these gradually led to more and more software (especially bulletin board systems) assuming the escape sequences worked, leading to almost all new terminals and emulator programs supporting them. , which sparked a variety of "clones," among the earliest and most popular of which was the much more affordable Zenith Z19 in 1979. The first popular video terminal to support these sequences was the Digital VT100 introduced in 1978. ![]() The name "ANSI escape sequence" dates from 1981 when ANSI adopted ECMA-48 as the standard ANSI X3.64 (and later, in 1997, withdrew it). It is also adopted by ISO and IEC as standard ISO/IEC 6429. ECMA-48 has been updated several times and the current edition is the 5th from 1991. It was a continuation of a series of character coding standards, the first one being ECMA-6 from 1961, a 7-bit standard from which ASCII originates. The first standard for ANSI escape sequences was ECMA-48, adopted in 1976. In addition, most designs required sending numbers (such as row & column) as the binary values of the characters for some programming languages and for systems that did not use ASCII internally it was often difficult or impossible to turn a number into the correct character. As these sequences were all different, elaborate libraries such as termcap had to be created so programs could use the same API for all of them. 8 Illegal and ambiguous sequences in useĪlmost all manufacturers of video terminals added vendor-specific escape sequences to do operations such as placing the cursor at arbitrary positions on the screen.
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