fish-shell/doc_src/cmds/fish_key_reader.rst

.. _cmd-fish_key_reader:

fish_key_reader - explore what characters keyboard keys send
============================================================

Synopsis
--------

.. synopsis::

    fish_key_reader [OPTIONS]

Description
-----------

:program:`fish_key_reader` is used to explain how you would bind a certain key sequence. By default, it prints the :doc:`bind <bind>` command for one key sequence read interactively over standard input.

If the character sequence matches a special key name (see ``bind --key-names``),  both ``bind CHARS ...`` and ``bind -k KEYNAME ...`` usage will be shown. In verbose mode (enabled by passing ``--verbose``), additional details about the characters received, such as the delay between chars, are written to standard error.

The following options are available:

**-c** or **--continuous**
    Begins a session where multiple key sequences can be inspected. By default the program exits after capturing a single key sequence.

**-V** or **--verbose**
    Tells fish_key_reader to output timing information and explain the sequence in more detail.

**-h** or **--help**
    Displays help about using this command.

**-v** or **--version**
    Displays the current :program:`fish` version and then exits.

Usage Notes
-----------

In verbose mode, the delay in milliseconds since the previous character was received is included in the diagnostic information written to standard error. This information may be useful to determine the optimal ``fish_escape_delay_ms`` setting or learn the amount of lag introduced by tools like ``ssh``, ``mosh`` or ``tmux``.

``fish_key_reader`` intentionally disables handling of many signals. To terminate ``fish_key_reader`` in ``--continuous`` mode do:

- press :kbd:`Control`\ +\ :kbd:`C` twice, or
- press :kbd:`Control`\ +\ :kbd:`D` twice, or
- type ``exit``, or
- type ``quit``

Example
-------

::

   > fish_key_reader
   Press a key:
   # press up-arrow
   bind \e\[A 'do something'

   > fish_key_reader --verbose
   Press a key:
   # press alt+enter
              hex:   1B  char: \e
   (  0.027 ms)  hex:    D  char: \cM  (or \r)
   bind \e\r 'do something'
docs: Add labels to all commands This allows us to use :ref: references, which don't require hardcoding it as html [ci skip] 2019-03-31 09:05:09 +00:00			`.. _cmd-fish_key_reader:`

Switch command docs from \section to reStructuredText 2018-12-17 01:39:33 +00:00			`fish_key_reader - explore what characters keyboard keys send`
Fix command section separator line lengths 2019-01-03 04:10:47 +00:00			`============================================================`
Switch command docs from \section to reStructuredText 2018-12-17 01:39:33 +00:00
Migrate the 'synopsis' sections to .rst format 2018-12-18 01:58:24 +00:00			`Synopsis`
			`--------`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs synopsis: add HTML highlighing and automate manpage markup Recent synopsis changes move from literal code blocks to [RST line blocks]. This does not translate well to HTML: it's not rendered in monospace, so aligment is lost. Additionally, we don't get syntax highlighting in HTML, which adds differences to our code samples which are highlighted. We hard-wrap synopsis lines (like code blocks). To align continuation lines in manpages we need [backslashes in weird places]. Combined with the *, , and `` markup, it's a bit hard to get the alignment right. Fix these by moving synopsis sources back to code blocks and compute HTML syntax highlighting and manpage markup with a custom Sphinx extension. The new Pygments lexer can tokenize a synopsis and assign the various highlighting roles, which closely matches fish's syntax highlighing: - command/keyword (dark blue) - parameter (light blue) - operator like and/or/not/&&/\|\| (cyan) - grammar metacharacter (black) For manpage output, we don't project the fish syntax highlighting but follow the markup convention in GNU's man(1): bold text type exactly as shown. italic text replace with appropriate argument. To make it easy to separate these two automatically, formalize that (italic) placeholders must be uppercase; while all lowercase text is interpreted literally (so rendered bold). This makes manpages more consistent, see string-join(1) and and(1). Implementation notes: Since we want manpage formatting but Sphinx's Pygments highlighing plugin does not support manpage output, add our custom "synopsis" directive. This directive parses differently when manpage output is specified. This means that the HTML and manpage build processes must not share a cache, because the parsed doctrees are cached. Work around this by using separate cache locations for build targets "sphinx-docs" (which creates HTML) and "sphinx-manpages". A better solution would be to only override Sphinx's ManualPageBuilder but that would take a bit more code (ideally we could override ManualPageWriter but Sphinx 4.3.2 doesn't really support that). --- Alternative solution: stick with line blocks but use roles like :command: or :option: (or custom ones). While this would make it possible to produce HTML that is consistent with code blocks (by adding a bit of CSS), the source would look uglier and is harder to maintain. (Let's say we want to add custom formatting to the [\|] metacharacters in HTML. This is much easier with the proposed patch.) --- [RST line blocks]: https://docutils.sourceforge.io/docs/ref/rst/restructuredtext.html#line-blocks [backslashes in weird places]: https://github.com/fish-shell/fish-shell/pull/8626#discussion_r782837750 2022-01-09 14:09:46 +00:00			`.. synopsis::`

			`fish_key_reader [OPTIONS]`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
Convert \\subsection sections into rst format 2018-12-19 02:44:30 +00:00			`Description`
Fix command section separator line lengths 2019-01-03 04:10:47 +00:00			`-----------`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs: Use :doc: role when linking to commands This makes it so we link to the very top of the document instead of a special anchor we manually include. So clicking e.g. :doc:`string <cmds/string>` will link you to cmds/string.html instead of cmds/string.html#cmd-string. I would love to have a way to say "this document from the root of the document path", but that doesn't appear to work, I tried `/cmds/string`. So we'll just have to use cmds/string in normal documents and plain `string` from other commands. 2022-09-23 17:57:49 +00:00			:program:`fish_key_reader` is used to explain how you would bind a certain key sequence. By default, it prints the :doc:`bind <bind>` command for one key sequence read interactively over standard input.
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs: omnibus cleanup Includes harmonizing the display of options and arguments, standardising terminology, using the envvar directive more broadly, adding help options to all commands that support them, simplifying some language, and tidying up multiple formatting issues. string documentation is not changed. 2022-03-11 16:18:41 +00:00			If the character sequence matches a special key name (see ``bind --key-names``), both ``bind CHARS ...`` and ``bind -k KEYNAME ...`` usage will be shown. In verbose mode (enabled by passing ``--verbose``), additional details about the characters received, such as the delay between chars, are written to standard error.
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
			`The following options are available:`

docs: standardise on definition lists for options Harmonizes the option listing including formatting in a similar manner to the synopsis of each entry. 2022-03-11 15:56:20 +00:00			`-c or --continuous`
			`Begins a session where multiple key sequences can be inspected. By default the program exits after capturing a single key sequence.`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs: standardise on definition lists for options Harmonizes the option listing including formatting in a similar manner to the synopsis of each entry. 2022-03-11 15:56:20 +00:00			`-V or --verbose`
			`Tells fish_key_reader to output timing information and explain the sequence in more detail.`
Make fish_key_reader's output simpler (#8467) * fish_key_reader: Simplify default output It now only prints the bind statement. Timing information and such is relegated to a separate "verbose" mode. * Adjust fish_key_reader docs * Adjust tests 2021-11-22 16:22:22 +00:00
docs: standardise on definition lists for options Harmonizes the option listing including formatting in a similar manner to the synopsis of each entry. 2022-03-11 15:56:20 +00:00			`-h or --help`
			`Displays help about using this command.`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs: standardise on definition lists for options Harmonizes the option listing including formatting in a similar manner to the synopsis of each entry. 2022-03-11 15:56:20 +00:00			`-v or --version`
			Displays the current :program:`fish` version and then exits.
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
Convert \\subsection sections into rst format 2018-12-19 02:44:30 +00:00			`Usage Notes`
Fix command section separator line lengths 2019-01-03 04:10:47 +00:00			`-----------`
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs: omnibus cleanup Includes harmonizing the display of options and arguments, standardising terminology, using the envvar directive more broadly, adding help options to all commands that support them, simplifying some language, and tidying up multiple formatting issues. string documentation is not changed. 2022-03-11 16:18:41 +00:00			In verbose mode, the delay in milliseconds since the previous character was received is included in the diagnostic information written to standard error. This information may be useful to determine the optimal ``fish_escape_delay_ms`` setting or learn the amount of lag introduced by tools like ``ssh``, ``mosh`` or ``tmux``.
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
Switch backticks to double backticks for rst compatibility 2018-12-19 20:02:45 +00:00			``fish_key_reader`` intentionally disables handling of many signals. To terminate ``fish_key_reader`` in ``--continuous`` mode do:
Copy doc_src to sphinx_doc_src and add a TOC 2018-12-16 21:08:41 +00:00
docs: Fix spacing on key combinations 2020-03-20 05:47:22 +00:00			- press :kbd:`Control`\ +\ :kbd:`C` twice, or
			- press :kbd:`Control`\ +\ :kbd:`D` twice, or
Switch backticks to double backticks for rst compatibility 2018-12-19 20:02:45 +00:00			- type ``exit``, or
			- type ``quit``
Make fish_key_reader's output simpler (#8467) * fish_key_reader: Simplify default output It now only prints the bind statement. Timing information and such is relegated to a separate "verbose" mode. * Adjust fish_key_reader docs * Adjust tests 2021-11-22 16:22:22 +00:00
			`Example`
			`-------`

			`::`

			`> fish_key_reader`
			`Press a key:`
			`# press up-arrow`
			`bind \e\[A 'do something'`

			`> fish_key_reader --verbose`
			`Press a key:`
			`# press alt+enter`
fish_key_reader: Humanize key descriptions This used to print all codepoints outside of the ASCII range (i.e. above 0x80) in \uXXXX or \UYYYYYYYY notation. That's quite awkward, considering that this is about keys that are being pressed, and many keyboards have actual symbols for these on them - I have an "ö" key, so I would like to use `bind ö` and not `bind \u00F6`. So we go by iswgraph. On a slightly different note, `\e` was written as `\c[ (or \e)`. I do not believe anyone really uses `\c[` (the `[` would need to be escaped!), and it's confusing and unnecessary to even mention that. 2023-08-26 07:40:53 +00:00			`hex: 1B char: \e`
Make fish_key_reader's output simpler (#8467) * fish_key_reader: Simplify default output It now only prints the bind statement. Timing information and such is relegated to a separate "verbose" mode. * Adjust fish_key_reader docs * Adjust tests 2021-11-22 16:22:22 +00:00			`( 0.027 ms) hex: D char: \cM (or \r)`
			`bind \e\r 'do something'`