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       console_codes - Linux console escape and control sequences


       The  Linux  console implements a large subset of the VT102 and ECMA-48/ISO 6429/ANSI X3.64
       terminal controls, plus certain private-mode sequences for  changing  the  color  palette,
       character-set  mapping,  and  so on.  In the tabular descriptions below, the second column
       gives ECMA-48 or DEC mnemonics (the latter if prefixed with DEC) for the  given  function.
       Sequences without a mnemonic are neither ECMA-48 nor VT102.

       After  all  the normal output processing has been done, and a stream of characters arrives
       at the console driver for actual printing, the first thing that happens is  a  translation
       from the code used for processing to the code used for printing.

       If  the  console is in UTF-8 mode, then the incoming bytes are first assembled into 16-bit
       Unicode codes.  Otherwise, each byte is transformed according to the current mapping table
       (which  translates  it  to  a  Unicode  value).   See the Character Sets section below for

       In the normal case, the Unicode value is converted to a font index, and this is stored  in
       video  memory,  so  that  the  corresponding  glyph (as found in video ROM) appears on the
       screen.  Note that the use of Unicode (and the design of the PC hardware) allows us to use
       512 different glyphs simultaneously.

       If  the  current  Unicode  value is a control character, or we are currently processing an
       escape sequence, the value will treated specially.  Instead of being turned  into  a  font
       index  and rendered as a glyph, it may trigger cursor movement or other control functions.
       See the Linux Console Controls section below for discussion.

       It is generally not good practice to hard-wire terminal  controls  into  programs.   Linux
       supports  a  terminfo(5)  database of terminal capabilities.  Rather than emitting console
       escape sequences by hand, you will almost always  want  to  use  a  terminfo-aware  screen
       library or utility such as ncurses(3), tput(1), or reset(1).

   Linux console controls
       This section describes all the control characters and escape sequences that invoke special
       functions (i.e., anything other than writing a glyph at the current  cursor  location)  on
       the Linux console.

       Control characters

       A  character  is  a  control  character if (before transformation according to the mapping
       table) it has one of the 14 codes 00 (NUL), 07 (BEL), 08 (BS), 09 (HT), 0a (LF), 0b  (VT),
       0c (FF), 0d (CR), 0e (SO), 0f (SI), 18 (CAN), 1a (SUB), 1b (ESC), 7f (DEL).  One can set a
       "display control characters" mode (see below), and allow 07, 09, 0b,  18,  1a,  7f  to  be
       displayed  as  glyphs.   On  the other hand, in UTF-8 mode all codes 00–1f are regarded as
       control characters, regardless of any "display control characters" mode.

       If we have a control character, it is acted upon immediately and then discarded  (even  in
       the  middle  of  an  escape  sequence)  and  the  escape  sequence continues with the next
       character.  (However, ESC starts a new  escape  sequence,  possibly  aborting  a  previous
       unfinished  one,  and  CAN  and  SUB  abort  any escape sequence.)  The recognized control
       characters are BEL, BS, HT, LF, VT, FF, CR, SO, SI, CAN, SUB, ESC, DEL, CSI.  They do what
       one would expect:

       BEL (0x07, ^G) beeps;

       BS (0x08, ^H) backspaces one column (but not past the beginning of the line);

       HT  (0x09,  ^I) goes to the next tab stop or to the end of the line if there is no earlier
              tab stop;

       LF (0x0A, ^J), VT (0x0B, ^K) and FF (0x0C, ^L) all give a linefeed, and if LF/NL (new-line
              mode) is set also a carriage return;

       CR (0x0D, ^M) gives a carriage return;

       SO (0x0E, ^N) activates the G1 character set;

       SI (0x0F, ^O) activates the G0 character set;

       CAN (0x18, ^X) and SUB (0x1A, ^Z) interrupt escape sequences;

       ESC (0x1B, ^[) starts an escape sequence;

       DEL (0x7F) is ignored;

       CSI (0x9B) is equivalent to ESC [.

       ESC- but not CSI-sequences

       ESC c     RIS      Reset.
       ESC D     IND      Linefeed.
       ESC E     NEL      Newline.
       ESC H     HTS      Set tab stop at current column.
       ESC M     RI       Reverse linefeed.
       ESC Z     DECID    DEC private identification. The kernel returns the
                          string  ESC [ ? 6 c, claiming that it is a VT102.
       ESC 7     DECSC    Save   current    state    (cursor    coordinates,
                          attributes, character sets pointed at by G0, G1).
       ESC 8     DECRC    Restore state most recently saved by ESC 7.
       ESC [     CSI      Control sequence introducer
       ESC %              Start sequence selecting character set
       ESC % @               Select default (ISO 646 / ISO 8859-1)
       ESC % G               Select UTF-8
       ESC % 8               Select UTF-8 (obsolete)
       ESC # 8   DECALN   DEC screen alignment test - fill screen with E's.
       ESC (              Start sequence defining G0 character set
       ESC ( B               Select default (ISO 8859-1 mapping)
       ESC ( 0               Select VT100 graphics mapping
       ESC ( U               Select null mapping - straight to character ROM
       ESC ( K               Select user mapping - the map that is loaded by
                             the utility mapscrn(8).
       ESC )              Start sequence defining G1
                          (followed by one of B, 0, U, K, as above).
       ESC >     DECPNM   Set numeric keypad mode
       ESC =     DECPAM   Set application keypad mode
       ESC ]     OSC      (Should  be:  Operating  system  command)  ESC ] P
                          nrrggbb: set palette, with parameter  given  in  7
                          hexadecimal  digits after the final P :-(.  Here n
                          is the color  (0–15),  and  rrggbb  indicates  the
                          red/green/blue  values  (0–255).   ESC  ] R: reset

       ECMA-48 CSI sequences

       CSI (or ESC [) is followed by a sequence of  parameters,  at  most  NPAR  (16),  that  are
       decimal  numbers  separated by semicolons.  An empty or absent parameter is taken to be 0.
       The sequence of parameters may be preceded by a single question mark.

       However, after CSI [ (or ESC [ [) a single character is read and this entire  sequence  is
       ignored.  (The idea is to ignore an echoed function key.)

       The action of a CSI sequence is determined by its final character.

       @   ICH       Insert the indicated # of blank characters.
       A   CUU       Move cursor up the indicated # of rows.

       B   CUD       Move cursor down the indicated # of rows.
       C   CUF       Move cursor right the indicated # of columns.
       D   CUB       Move cursor left the indicated # of columns.
       E   CNL       Move cursor down the indicated # of rows, to column 1.
       F   CPL       Move cursor up the indicated # of rows, to column 1.
       G   CHA       Move cursor to indicated column in current row.
       H   CUP       Move cursor to the indicated row, column (origin at 1,1).
       J   ED        Erase display (default: from cursor to end of display).
                     ESC [ 1 J: erase from start to cursor.
                     ESC [ 2 J: erase whole display.
                     ESC [ 3 J: erase whole display including scroll-back
                                buffer (since Linux 3.0).
       K   EL        Erase line (default: from cursor to end of line).
                     ESC [ 1 K: erase from start of line to cursor.
                     ESC [ 2 K: erase whole line.
       L   IL        Insert the indicated # of blank lines.
       M   DL        Delete the indicated # of lines.
       P   DCH       Delete the indicated # of characters on current line.
       X   ECH       Erase the indicated # of characters on current line.
       a   HPR       Move cursor right the indicated # of columns.
       c   DA        Answer ESC [ ? 6 c: "I am a VT102".
       d   VPA       Move cursor to the indicated row, current column.
       e   VPR       Move cursor down the indicated # of rows.
       f   HVP       Move cursor to the indicated row, column.
       g   TBC       Without parameter: clear tab stop at current position.
                     ESC [ 3 g: delete all tab stops.
       h   SM        Set Mode (see below).
       l   RM        Reset Mode (see below).
       m   SGR       Set attributes (see below).
       n   DSR       Status report (see below).
       q   DECLL     Set keyboard LEDs.
                     ESC [ 0 q: clear all LEDs
                     ESC [ 1 q: set Scroll Lock LED
                     ESC [ 2 q: set Num Lock LED
                     ESC [ 3 q: set Caps Lock LED
       r   DECSTBM   Set scrolling region; parameters are top and bottom row.
       s   ?         Save cursor location.
       u   ?         Restore cursor location.
       `   HPA       Move cursor to indicated column in current row.

       ECMA-48 Set Graphics Rendition

       The  ECMA-48  SGR sequence ESC [ parameters m sets display attributes.  Several attributes
       can be set in the same sequence, separated by semicolons.   An  empty  parameter  (between
       semicolons or string initiator or terminator) is interpreted as a zero.

       param     result
       0         reset all attributes to their defaults
       1         set bold
       2         set half-bright (simulated with color on a color display)
       4         set  underscore (simulated with color on a color display)
                 (the colors used to simulate dim  or  underline  are  set
                 using ESC ] ...)
       5         set blink
       7         set reverse video
       10        reset  selected mapping, display control flag, and toggle
                 meta flag (ECMA-48 says "primary font").
       11        select null mapping,  set  display  control  flag,  reset
                 toggle meta flag (ECMA-48 says "first alternate font").
       12        select null mapping, set display control flag, set toggle
                 meta flag (ECMA-48 says "second  alternate  font").   The
                 toggle  meta  flag  causes  the  high bit of a byte to be
                 toggled before the mapping table translation is done.
       21        set underline; before Linux 4.17, this value  set  normal
                 intensity (as is done in many other terminals)

       22        set normal intensity
       24        underline off
       25        blink off
       27        reverse video off
       30        set black foreground
       31        set red foreground
       32        set green foreground
       33        set brown foreground
       34        set blue foreground
       35        set magenta foreground
       36        set cyan foreground
       37        set white foreground
       38        256/24-bit  foreground  color follows, shoehorned into 16
                 basic colors (before Linux 3.16: set underscore  on,  set
                 default foreground color)
       39        set  default  foreground  color  (before  Linux 3.16: set
                 underscore off, set default foreground color)
       40        set black background
       41        set red background
       42        set green background
       43        set brown background
       44        set blue background
       45        set magenta background
       46        set cyan background
       47        set white background
       48        256/24-bit background color follows,  shoehorned  into  8
                 basic colors
       49        set default background color
       90..97    set foreground to bright versions of 30..37
       100.107   set background, same as 40..47 (bright not supported)

       Commands 38 and 48 require further arguments:

       ;5;x       256  color:  values 0..15 are IBGR (black, red, green,
                  ... white), 16..231 a 6x6x6  color  cube,  232..255  a
                  grayscale ramp
       ;2;r;g;b   24-bit color, r/g/b components are in the range 0..255

       ECMA-48 Mode Switches

       ESC [ 3 h
              DECCRM (default off): Display control chars.

       ESC [ 4 h
              DECIM (default off): Set insert mode.

       ESC [ 20 h
              LF/NL (default off): Automatically follow echo of LF, VT or FF with CR.

       ECMA-48 Status Report Commands

       ESC [ 5 n
              Device status report (DSR): Answer is ESC [ 0 n (Terminal OK).

       ESC [ 6 n
              Cursor  position  report  (CPR):  Answer  is ESC [ y ; x R, where x,y is the cursor

       DEC Private Mode (DECSET/DECRST) sequences

       These are not described in ECMA-48.  We list  the  Set  Mode  sequences;  the  Reset  Mode
       sequences are obtained by replacing the final 'h' by 'l'.

       ESC [ ? 1 h
              DECCKM  (default  off): When set, the cursor keys send an ESC O prefix, rather than
              ESC [.

       ESC [ ? 3 h
              DECCOLM (default off = 80 columns): 80/132 col mode  switch.   The  driver  sources
              note that this alone does not suffice; some user-mode utility such as resizecons(8)
              has to change the hardware registers on the console video card.

       ESC [ ? 5 h
              DECSCNM (default off): Set reverse-video mode.

       ESC [ ? 6 h
              DECOM (default off): When set, cursor addressing is  relative  to  the  upper  left
              corner of the scrolling region.

       ESC [ ? 7 h
              DECAWM  (default  on):  Set autowrap on.  In this mode, a graphic character emitted
              after column 80 (or column 132 of DECCOLM is on) forces a wrap to the beginning  of
              the following line first.

       ESC [ ? 8 h
              DECARM (default on): Set keyboard autorepeat on.

       ESC [ ? 9 h
              X10  Mouse  Reporting  (default  off):  Set reporting mode to 1 (or reset to 0)—see

       ESC [ ? 25 h
              DECTECM (default on): Make cursor visible.

       ESC [ ? 1000 h
              X11 Mouse Reporting (default off): Set reporting mode to  2  (or  reset  to  0)—see

       Linux Console Private CSI Sequences

       The  following  sequences  are  neither  ECMA-48 nor native VT102.  They are native to the
       Linux console driver.  Colors are in SGR parameters: 0 = black, 1 = red, 2 =  green,  3  =
       brown, 4 = blue, 5 = magenta, 6 = cyan, 7 = white; 8–15 = bright versions of 0–7.

       ESC [ 1 ; n ]       Set color n as the underline color.
       ESC [ 2 ; n ]       Set color n as the dim color.
       ESC [ 8 ]           Make the current color pair the default attributes.
       ESC [ 9 ; n ]       Set screen blank timeout to n minutes.
       ESC [ 10 ; n ]      Set bell frequency in Hz.
       ESC [ 11 ; n ]      Set bell duration in msec.
       ESC [ 12 ; n ]      Bring specified console to the front.
       ESC [ 13 ]          Unblank the screen.
       ESC [ 14 ; n ]      Set the VESA powerdown interval in minutes.
       ESC [ 15 ]          Bring  the  previous  console  to  the front (since
                           Linux 2.6.0).
       ESC [ 16 ; n ]      Set  the  cursor  blink  interval  in  milliseconds
                           (since Linux 4.2).

   Character sets
       The  kernel  knows  about  4  translations of bytes into console-screen symbols.  The four
       tables are: a) Latin1 -> PC, b) VT100 graphics -> PC, c) PC -> PC, d) user-defined.

       There are two character sets, called G0 and G1, and one of them is the  current  character
       set.   (Initially  G0.)   Typing  ^N  causes  G1 to become current, ^O causes G0 to become

       These variables G0 and G1 point at a translation table, and can be changed  by  the  user.
       Initially they point at tables a) and b), respectively.  The sequences ESC ( B and ESC ( 0
       and ESC ( U and ESC ( K cause G0 to  point  at  translation  table  a),  b),  c)  and  d),
       respectively.  The sequences ESC ) B and ESC ) 0 and ESC ) U and ESC ) K cause G1 to point
       at translation table a), b), c) and d), respectively.

       The sequence ESC c causes a terminal reset, which is what you want if the  screen  is  all
       garbled.  The oft-advised "echo ^V^O" will make only G0 current, but there is no guarantee
       that G0 points at table a).  In some distributions there is a program reset(1)  that  just
       does  "echo  ^[c".   If  your  terminfo entry for the console is correct (and has an entry
       rs1=\Ec), then "tput reset" will also work.

       The user-defined mapping table can be set using mapscrn(8).  The result of the mapping  is
       that  if  a  symbol  c is printed, the symbol s = map[c] is sent to the video memory.  The
       bitmap that corresponds to s is found in the character  ROM,  and  can  be  changed  using

   Mouse tracking
       The  mouse  tracking  facility  is  intended  to  return  xterm(1)-compatible mouse status
       reports.  Because the console driver has no way to know the device or type of  the  mouse,
       these  reports  are  returned  in  the console input stream only when the virtual terminal
       driver receives a mouse update ioctl.  These ioctls must be  generated  by  a  mouse-aware
       user-mode application such as the gpm(8) daemon.

       The  mouse  tracking escape sequences generated by xterm(1) encode numeric parameters in a
       single character as value+040.  For example, '!' is 1.  The screen  coordinate  system  is

       The  X10 compatibility mode sends an escape sequence on button press encoding the location
       and the mouse button pressed.  It is enabled by sending ESC [ ? 9 h and disabled with  ESC
       [ ? 9 l.  On button press, xterm(1) sends ESC [ M bxy (6 characters).  Here b is button-1,
       and x and y are the x and y coordinates of the mouse when the button was pressed.  This is
       the same code the kernel also produces.

       Normal  tracking  mode  (not implemented in Linux 2.0.24) sends an escape sequence on both
       button press and release.  Modifier information is also sent.  It is  enabled  by  sending
       ESC  [  ?  1000  h and disabled with ESC [ ? 1000 l.  On button press or release, xterm(1)
       sends ESC [ M bxy.  The low two bits of b encode button information: 0=MB1 pressed,  1=MB2
       pressed,  2=MB3  pressed,  3=release.  The upper bits encode what modifiers were down when
       the button was pressed and are added together: 4=Shift, 8=Meta, 16=Control.  Again x and y
       are the x and y coordinates of the mouse event.  The upper left corner is (1,1).

   Comparisons with other terminals
       Many   different   terminal  types  are  described,  like  the  Linux  console,  as  being
       "VT100-compatible".  Here we discuss differences between the Linux  console  and  the  two
       most important others, the DEC VT102 and xterm(1).

       Control-character handling

       The VT102 also recognized the following control characters:

       NUL (0x00) was ignored;

       ENQ (0x05) triggered an answerback message;

       DC1 (0x11, ^Q, XON) resumed transmission;

       DC3  (0x13, ^S, XOFF) caused VT100 to ignore (and stop transmitting) all codes except XOFF
              and XON.

       VT100-like DC1/DC3 processing may be enabled by the terminal driver.

       The xterm(1) program (in VT100 mode) recognizes the control characters BEL,  BS,  HT,  LF,
       VT, FF, CR, SO, SI, ESC.

       Escape sequences

       VT100 console sequences not implemented on the Linux console:

       ESC N       SS2   Single shift 2. (Select G2 character set for the next
                         character only.)

       ESC O       SS3   Single shift 3. (Select G3 character set for the next
                         character only.)
       ESC P       DCS   Device control string (ended by ESC \)
       ESC X       SOS   Start of string.
       ESC ^       PM    Privacy message (ended by ESC \)
       ESC \       ST    String terminator
       ESC * ...         Designate G2 character set
       ESC + ...         Designate G3 character set

       The  program  xterm(1) (in VT100 mode) recognizes ESC c, ESC # 8, ESC >, ESC =, ESC D, ESC
       E, ESC H, ESC M, ESC N, ESC O, ESC P ... ESC \, ESC Z (it answers ESC [ ? 1 ; 2 c, "I am a
       VT100 with advanced video option") and ESC ^ ... ESC \ with the same meanings as indicated
       above.  It accepts ESC (, ESC ), ESC *,  ESC + followed by 0, A, B  for  the  DEC  special
       character and line drawing set, UK, and US-ASCII, respectively.

       The  user  can  configure  xterm(1) to respond to VT220-specific control sequences, and it
       will identify itself as a VT52, VT100, and up depending on the way it  is  configured  and

       It  accepts  ESC ] (OSC) for the setting of certain resources.  In addition to the ECMA-48
       string terminator (ST), xterm(1) accepts a BEL to terminate an OSC string.   These  are  a
       few of the OSC control sequences recognized by xterm(1):

       ESC ] 0 ; txt ST        Set icon name and window title to txt.
       ESC ] 1 ; txt ST        Set icon name to txt.
       ESC ] 2 ; txt ST        Set window title to txt.
       ESC ] 4 ; num; txt ST   Set ANSI color num to txt.
       ESC ] 10 ; txt ST       Set dynamic text color to txt.
       ESC ] 4 6 ; name ST     Change log file to name (normally disabled
                               by a compile-time option)
       ESC ] 5 0 ; fn ST       Set font to fn.

       It  recognizes  the  following with slightly modified meaning (saving more state, behaving
       closer to VT100/VT220):

       ESC 7  DECSC   Save cursor
       ESC 8  DECRC   Restore cursor

       It also recognizes

       ESC F          Cursor to lower left corner of screen (if enabled by
                      xterm(1)'s hpLowerleftBugCompat resource)
       ESC l          Memory lock (per HP terminals).
                      Locks memory above the cursor.
       ESC m          Memory unlock (per HP terminals).
       ESC n   LS2    Invoke the G2 character set.
       ESC o   LS3    Invoke the G3 character set.
       ESC |   LS3R   Invoke the G3 character set as GR.
                      Has no visible effect in xterm.
       ESC }   LS2R   Invoke the G2 character set as GR.
                      Has no visible effect in xterm.
       ESC ~   LS1R   Invoke the G1 character set as GR.
                      Has no visible effect in xterm.

       It also recognizes ESC % and provides a more  complete  UTF-8  implementation  than  Linux

       CSI Sequences

       Old  versions of xterm(1), for example, from X11R5, interpret the blink SGR as a bold SGR.
       Later versions which implemented  ANSI  colors,  for  example,  XFree86  3.1.2A  in  1995,
       improved this by allowing the blink attribute to be displayed as a color.  Modern versions
       of xterm implement blink SGR as blinking text and still allow colored text as an alternate
       rendering  of  SGRs.   Stock X11R6 versions did not recognize the color-setting SGRs until
       the X11R6.8  release,  which  incorporated  XFree86  xterm.   All  ECMA-48  CSI  sequences
       recognized  by  Linux  are  also  recognized by xterm, however xterm(1) implements several
       ECMA-48 and DEC control sequences not recognized by Linux.

       The xterm(1) program recognizes all of the DEC Private Mode sequences  listed  above,  but
       none  of  the Linux private-mode sequences.  For discussion of xterm(1)'s own private-mode
       sequences, refer to the Xterm Control Sequences document by Edward  Moy,  Stephen  Gildea,
       and  Thomas  E. Dickey available with the X distribution.  That document, though terse, is
       much longer than this manual page.  For a chronological overview,


       details changes to xterm.

       The vttest program


       demonstrates many of these control  sequences.   The  xterm(1)  source  distribution  also
       contains sample scripts which exercise other features.


       ESC 8 (DECRC) is not able to restore the character set changed with ESC %.


       In 2.0.23, CSI is broken, and NUL is not ignored inside escape sequences.

       Some  older  kernel  versions  (after  2.0)  interpret 8-bit control sequences.  These "C1
       controls" use codes between 128 and 159 to replace ESC  [,  ESC  ]  and  similar  two-byte
       control  sequence  initiators.   There  are  fragments  of  that in modern kernels (either
       overlooked or broken by changes to support UTF-8), but the  implementation  is  incomplete
       and should be regarded as unreliable.

       Linux "private mode" sequences do not follow the rules in ECMA-48 for private mode control
       sequences.  In particular,  those  ending  with  ]  do  not  use  a  standard  terminating
       character.   The  OSC  (set  palette)  sequence  is  a greater problem, since xterm(1) may
       interpret this as a control sequence which requires a string terminator (ST).  Unlike  the
       setterm(1) sequences which will be ignored (since they are invalid control sequences), the
       palette sequence will make xterm(1) appear to hang (though pressing  the  return-key  will
       fix  that).   To  accommodate  applications which have been hardcoded to use Linux control
       sequences, set the xterm(1) resource brokenLinuxOSC to true.

       An older version of this document  implied  that  Linux  recognizes  the  ECMA-48  control
       sequence for invisible text.  It is ignored.


       ioctl_console(2), charsets(7)


       This  page  is  part of release 5.05 of the Linux man-pages project.  A description of the
       project, information about reporting bugs, and the latest version of  this  page,  can  be
       found at