FISH-TERMINAL-COMPATIBILITY(1) fish-shell FISH-TERMINAL-COMPATIBILITY(1)
fish writes various control sequences to the terminal. Some must be
implemented to enable basic functionality, while others enable optional
features and may be ignored by the terminal.
The terminal must be able to parse Control Sequence Introducer (CSI) commands,
Operating System Commands (OSC) and optionally Device Control Strings (DCS).
These are defined by ECMA-48. If a valid CSI, OSC or DCS sequence does not
represent a command implemented by the terminal, the terminal must ignore it.
For historical reasons, OSC sequences may be terminated with \x07 instead of
\e\\.
Control sequences are denoted in a fish-like syntax. Special characters other
than \ are not escaped. Spaces are only added for readability and are not
part of the sequence. Placeholders are written as Ps for a number or Pt for
an arbitrary printable string.
NOTE: fish does not rely on your system's terminfo database. In this
document, terminfo (TI) codes are included for reference only.
REQUIRED COMMANDS
+---------+-------+---------------------+
|Sequence | TI | Description |
+---------+-------+---------------------+
|\r | n/a | Move cursor to the |
| | | beginning of the |
| | | line |
+---------+-------+---------------------+
|\n | cud1 | Move cursor down |
| | | one line. |
+---------+-------+---------------------+
|\e[ Ps A | cuu | Move cursor up Ps |
| | | columns, or one |
| | | column if no |
| | | parameter. |
+---------+-------+---------------------+
|\e[ Ps C | cuf | Move cursor to the |
| | | right Ps columns, |
| | | or one column if no |
| | | parameter. |
+---------+-------+---------------------+
|\x08 | cub1 | Move cursor one |
| | | column to the left. |
+---------+-------+---------------------+
|\e[ Ps D | cub | Move cursor to the |
| | | left Ps times. |
+---------+-------+---------------------+
|\e[H | cup | Set cursor position |
| | | (no parameters |
| | | means: move to row |
| | | 1, column 1). |
+---------+-------+---------------------+
|\e[K | el | Clear to end of |
| | | line. |
+---------+-------+---------------------+
|\e[J | ed | Clear to the end of |
| | | screen. |
+---------+-------+---------------------+
|\e[2J | clear | Clear the screen. |
+---------+-------+---------------------+
|\e[0c | | Request Primary |
| | | Device Attribute. |
| | | The terminal must |
| | | respond with a CSI |
| | | command that starts |
| | | with the ? |
| | | parameter byte (so |
| | | a sequence starting |
| | | with \e[?) and has |
| | | c as final byte. |
| | | Failure to |
| | | implement this will |
| | | cause a brief pause |
| | | at startup followed |
| | | by a warning. For |
| | | the time being, |
| | | both can be turned |
| | | off by turning off |
| | | the query-terminal |
| | | feature flag <# |
| | | featureflags>. |
+---------+-------+---------------------+
|n/a | am | Soft wrap text at |
| | | screen width. |
+---------+-------+---------------------+
|n/a | xenl | Printing to the |
| | | last column does |
| | | not move the cursor |
| | | to the next line. |
| | | Verify this by |
| | | running printf |
| | | %0"$COLUMNS"d 0; |
| | | sleep 3 |
+---------+-------+---------------------+
OPTIONAL COMMANDS
+--------------------+-------------+-----------------------------------------------------------------------------------+
|Sequence | TI | Description |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\t | it | Move the cursor to the next tab stop (a 8 columns). This is mainly relevant if |
| | | your prompt includes tabs. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[m | sgr0 | Turn off bold/dim/italic/underline/strikethrough/reverse attribute modes and |
| | | select default colors. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[1m | bold | Enter bold mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[2m | dim | Enter dim mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[3m | sitm | Enter italic mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[4m | smul | Enter underline mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[4:2m | Su | Enter double underline mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[4:3m | Su | Enter curly underline mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[4:4m | Su | Enter dotted underline mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[4:5m | Su | Enter dashed underline mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[7m | rev | Enter reverse video mode (swap foreground and background colors). |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[9m | smxx | Enter strikethrough mode |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[23m | ritm | Exit italic mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[24m | rmul | Exit underline mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[29m | rmxx | Exit strikethrough mode. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[38;5; Ps m | setaf | Select foreground color Ps from the 256-color-palette. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[48;5; Ps m | setab | Select background color Ps from the 256-color-palette. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[58:5: Ps m | Su | Select underline color Ps from the 256-color-palette. |
|(note: colons not | | |
|semicolons) | | |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[ Ps m | setaf setab | Select foreground/background color. This uses a color in the aforementioned |
| | | 256-color-palette, based on the range that contains the parameter: 30-37 maps to |
| | | foreground 0-7, 40-47 maps to background 0-7, 90-97 maps to foreground 8-15 and |
| | | 100-107 maps to background 8-15. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[38;2; Ps ; Ps ; | | Select foreground color from 24-bit RGB colors. |
|Ps m | | |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[48;2; Ps ; Ps ; | | Select background color from 24-bit RGB colors. |
|Ps m | | |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[49m | | Reset background color to the terminal's default. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[58:2:: Ps : Ps : | Su | Select underline color from 24-bit RGB colors. |
|Ps m (note: colons | | |
|not semicolons) | | |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[59m | Su | Reset underline color to the default (follow the foreground color). |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[ Ps S | indn | Scroll up the content (not the viewport) Ps lines (called SCROLL UP / SU by |
| | | ECMA-48 and "scroll forward" by terminfo). When fish detects support for this |
| | | feature, status test-terminal-features scroll-content-up <# |
| | | status-test-terminal-features> will return 0, which enables the ctrl-l binding to |
| | | use the scrollback-push <#special-input-functions-scrollback-push> special input |
| | | function. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[= Ps u, \e[? Ps | n/a | Enable the kitty keyboard protocol. |
|u | | |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[6n | n/a | Request cursor position report. The response must be of the form \e[ Ps ; Ps R |
| | | where the first parameter is the row number and the second parameter is the |
| | | column number. Both start at 1. This is used for truncating multiline |
| | | autosuggestions at the screen's bottom edge, by the scrollback-push <# |
| | | special-input-functions-scrollback-push> special input function, and inside |
| | | terminals that implement the OSC 133 click_events feature. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[ \x20 q | Se | Reset cursor style to the terminal's default. This is not used as of today but |
| | | may be in future. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[ Ps \x20 q | Ss | Set cursor style (DECSCUSR); Ps is 2, 4 or 6 for block, underscore or line shape. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[ Ps q | n/a | Request terminal name and version (XTVERSION). This is only used for temporary |
| | | workarounds for incompatible terminals. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?25h | cvvis | Enable cursor visibility (DECTCEM). |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?1004h | n/a | Enable focus reporting. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?1004l | n/a | Disable focus reporting. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?1049h | n/a | Enable alternate screen buffer. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?1049l | n/a | Disable alternate screen buffer. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?2004h | | Enable bracketed paste. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?2004l | | Disable bracketed paste. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?2031h | | Enable unsolicited color theme reporting . When enabled, the terminal |
| | | should send \e[?997;1n or \e[?997;2n whenever its color theme has changed. This |
| | | prompts fish to query for background color. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e[?2031l | | Disable unsolicited color theme reporting. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]0; Pt \e\\ | ts | Set terminal window title (OSC 0). Used in fish_title <>. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]2; Pt \e\\ | ts | Set terminal tab title (OSC 1). Used in fish_tab_title <>. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]7;file:// Pt / | | Report working directory (OSC 7). Since the terminal may be running on a |
|Pt \e\\ | | different system than a (remote) shell, the hostname (first parameter) will not |
| | | be localhost. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]8;; Pt \e\\ | | Create a hyperlink (OSC 8) . This is used in fish's man pages. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]11;?\e\\ | n/a | Query background color. A valid response would be of the form \e]11;rgb: Pt / Pt |
| | | / Pt \e\\ or \e]11;rgba: Pt / Pt / Pt / Pt\e\\ where the first three parameters |
| | | consist of one to four hex digits each, representing red, blue and green |
| | | components. This is used to populate fish_terminal_color_theme <# |
| | | envvar-fish_terminal_color_theme>, which is used to select a theme variant <# |
| | | fish-config-theme-files> optimized for the terminal's color theme. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]52;c; Pt \e\\ | | Copy to clipboard (OSC 52). Used by fish_clipboard_copy <>. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]133;A; | | Mark prompt start (OSC 133), with kitty's click_events extension. The |
|click_events=1\e\\ | | click_events extension enables mouse clicks to move the cursor or select pager |
| | | items, assuming that cursor position reporting is available. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]133;B\e\\ | | Mark prompt end (OSC 133). |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]133;C; | | Mark command start (OSC 133), with kitty's cmdline_url extension whose parameter |
|cmdline_url= Pt | | is the URL-encoded command line. |
|\e\\ | | |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\e]133;D; Ps \e\\ | | Mark command end (OSC 133); Ps is the exit status. |
+--------------------+-------------+-----------------------------------------------------------------------------------+
|\eP+q Pt \e\\ | | Request terminfo capability (XTGETTCAP). The parameter is the capability's |
| | | hex-encoded terminfo code. The response must be of the form \eP1+q Pt \e\\ |
| | | ("boolean") or \eP1+q Pt = Pt \e\\ ("string"). In either variant, the first |
| | | parameter must be the same as the request parameter. fish queries the following |
| | | string capabilities: 0.0 o 2 indn The response's second parameter is ignored. o 2 |
| | | query-os-name (for status terminal-os <#status-terminal-os>) Terminals running on |
| | | Unix should respond with the hex encoding of $(uname -s) as second parameter. 0u |
+--------------------+-------------+-----------------------------------------------------------------------------------+
DCS COMMANDS AND GNU SCREEN
DCS parsing is optional because fish temporarily switches to the
alternate screen before printing any DCS commands. However, since GNU
screen neither allows turning on the alternate screen buffer by
default, nor treats DCS commands in a compatible way, fish's initial
prompt may be garbled by a DCS payload like +q696e646e. For the time
being, fish works around this by checking for presence of the STY
environment variable. If that doesn't work for some reason, you can
add this to your ~/.screenrc:
altscreen on
Or add this to your config.fish:
function GNU-screen-workaround --on-event fish_prompt
commandline -f repaint
functions --erase GNU-screen-workaround
end
UNICODE CODEPOINTS
By default, fish outputs the following non-ASCII characters:
x o - ' ` " " <- -> ^ v
as well as control pictures (U+2400 through U+241F), and
locale-specific ones in translated strings <#variables-locale>.
Author
fish-shell developers
Copyright
fish-shell developers
4.5 February 17, 2026
FISH-TERMINAL-COMPATIBILITY(1)