Emacs NEWS.27

The command-line argument '–socket-name' overrides it. (The same behavior as for the pre-existing 'EMACS_SERVERFILE' variable.)

This is used as the directory for client/server sockets, if Emacs is running on a platform or environment that sets the 'XDG_RUNTIMEDIR' environment variable to indicate where session sockets should go. To get the old, less-secure behavior, you can set the 'EMACS_SOCKETNAME' environment variable to an appropriate value.

(Instead you can use Tramp methods to run root commands in a non-root Emacs.)

and directory-local variables.

「with-connection-local-profiles」. No argument PROFILES needed any longer.

now prompts the user for the directory containing the desktop file.

and user options display-line-numbers-major-tick and display-line-numbers-minor-tick can be used to highlight the line numbers of lines multiple of certain numbers.

an offset to absolute line numbers.

This command can now output wiki and mediawiki format tables.

be ignored has been added via the 「goto-address-uri-schemes-ignored」 variable.

You can use this new user option to control indentation of arguments of \emph, \footnote, and similar commands.

This is because on the one hand it suffers from misbehavior in corner cases that have plagued it for years, and on the other hand experience indicates that it doesn't bring any measurable benefit.

new command that will recompile the file previously compiled with 'M-x byte-compile-file' and the like.

be functions.

nil, but instead of scrolling the current line to the top of the screen when there is no left fringe, it inserts a visible arrow before column zero.

be used to transform file name matches compilation output, and remove known false positives being recognized as warnings/errors.

its functions.

to allow controlling how the conversion to text is done.

to avoid conflicts with image-mode key 's'. The new key 'c' still has good mnemonics of "cut", "clip", "crop".

names match certain regular expressions as big. Ido won't attempt to list the contents of such directories when completing file names.

This option allows control of how the 'M-<' command works in the minibuffer. If non-nil, point will move to the end of the prompt (if point is after the end of the prompt). The default is nil, which preserves the original behavior of 'M-<' moving to the beginning of the prompt.

the end of the minibuffer instead of hiding the minibuffer by the echo area display. The new user option minibuffer-message-clear-timeout controls how messages displayed in this situation are removed from the minibuffer. To revert to previous behavior, where echo-area messages temporarily overwrote the minibuffer contents until the user typed something, set set-message-function and clear-message-function to nil.

at the end of the active minibuffer. To disable this, remove minibuffer-error-initialize from minibuffer-setup-hook.

a character using the minibuffer by read-char-from-minibuffer.

This happens upon moving off the edge of the frame.

The new command windmove-display-default-keybindings binds default keys with provided modifiers (by default, Shift-Meta) to the commands that display the next buffer in the window at the specified direction. This is like windmove-default-keybindings that binds keys to commands that select the window in the specified direction, but additionally it displays the buffer from the next command in that window. For example, 'S-M-right C-h i' displays the "Info" buffer in the right window, creating the window if necessary. A special key can be customized to display the buffer in the same window, for example, 'S-M-0 C-h e' displays the "Messages" buffer in the same window. 'S-M-t C-h r' displays the Emacs manual in a new tab.

The new command windmove-delete-default-keybindings binds default keys with provided prefix (by default, 【C-x】) and modifiers (by default, 'Shift') to the commands that delete the window in the specified direction. For example, 'C-x S-down' deletes the window below. With a prefix arg 【C-u】, also kills the buffer in that window. With 【M-0】, deletes the selected window and selects the window that was in the specified direction.

to the commands that swap the states of the selected window with the window in the specified direction.

That includes the user option 「windmove-window-distance-delta」 and the functions 「windmove-coord-add」, 「windmove-constrain-to-range」, 「windmove-constrain-around-range」, 「windmove-frame-edges」, 「windmove-constrain-loc-for-movement」, 「windmove-wrap-loc-for-movement」, 「windmove-reference-loc」 and 「windmove-other-window-loc」.

「fileloop-revert-buffers」.

「tags-loop-operate」 and 「tags-loop-scan」 variables are now obsolete; use the new fileloop-initialize and 「fileloop-continue」 functions instead.

In 「bibtex-mode-map」, forward-paragraph and backward-paragraph are remapped to these, respectively.

It is by default bound to '* N'.

command itself, not how many files are marked in total.

dired-do-copy and dired-rename-file should create non-existent directories in the destination.

or one of the most recently visited windows with a Dired buffer.

Dired performs file renaming using underlying version control system.

dired-do-compress-to.

permissions of such files with a special face 「dired-set-id」.

pipes, block devices and character devices.

The default value is 「find-dired-sort-by-filename」.

When non-nil, this user option causes the VC commands to communicate with the repository via Tor's proxy, using the 'torsocks' wrapper script. The default is nil.

This generates ChangeLog entries from the VC fileset diff.

If a ChangeLog file doesn't exist, and if the new user option 「add-log-dont-create-changelog-file」 is non-nil (which is the default), commands such as 【C-x 4 a】 will add log entries to a suitable named temporary buffer. (An existing ChangeLog file will still be used if it exists.) Set the user option to nil to get the previous behavior of always creating a buffer that visits a ChangeLog file.

buffers will delete the marked files (or if no files are marked, the file under point). This command does not notify the VC backend, and is mostly useful for unregistered files.

This new user option allows customizing the default arguments passed to 「git-grep」 when vc-git-grep is used.

When some files are marked, only those are stashed. When no files are marked, all modified files are stashed, as before.

Controlled by user option vc-git-show-stash. Default t means show the entire list as before. An integer value limits the list length (but still allows you to show the entire list via the button).

vc-git-stash and vc-git-stash-snapshot can now be run using 'C' and 'S' respectively, including when there are no stashes.

Code that attempted to invoke smerge-mode when visiting an Hg file with conflicts existed in earlier versions of Emacs, but incorrectly never detected a conflict due to invalid assumptions about cached values.

The 【C-x v h】 command now works in buffers that visit files controlled by Hg.

you invoke 【C-x v m】 (vc-merge).

instead of revision numbers as completion candidates when it prompts for a revision.

It specifies switches to pass to Hg's 'revert' command.

and compares their entire trees.

print diffs and logs between the merge base (common ancestor) of two given revisions.

in the revision log, and displays matched log entries in the log buffer. For example, 'M-x vc-log-search RET bug#36644 RET' displays all entries whose log messages match the bug number. With a prefix argument asks for a command, so for example, 'C-u M-x vc-log-search RET git log -1 f302475 RET' will display just one log entry found by its revision number.

If you invoke 【C-x v L】 (vc-print-root-log) with a numeric argument of 1, as in 'C-1 C-x v L' or 'C-u 1 C-x v L', it asks for a revision ID, and shows its log entry together with the diffs introduced by the revision's commit. (For some less capable VCSes, only the log entry is shown.)

With non-nil, vc-find-revision doesn't write the created buffer to file.

Set the new user option diff-font-lock-prettify to t for that, see below under "Diff mode".

rather than a file, in non-interactive calls. This change was made in Emacs 24.1, but wasn't documented until now.

To disable refinement, set the new user option diff-refine to nil. To get back the old behavior where hunks are refined as you navigate through a diff, set diff-refine to the symbol 'navigate'.

It is no longer enabled by default and binding it no longer has any effect.

Fragments of source in Diff hunks are now by default highlighted according to the appropriate major mode. Customize the new user option diff-font-lock-syntax to nil to disable this.

To enable it, set the new user option diff-font-lock-prettify to t. On GUI frames, this option also displays the insertion and deletion indicators on the left fringe.

of the file under version control if point is on an old changed line, or to the new revision of the file otherwise.

The function 'texinfo-insert-dwim-@ref', bound to 'C-c C-c r' by default, inserts one of three types of references based on the text surrounding point, namely '@pxref' near a parenthesis, '@xref' at the start of a sentence or at '(point-min)', else '@ref'.

It now treats the optional 2nd argument to mean that the URL should be shown in the currently selected window.

links to most ordinary special-mode buffers that display text that have URLs embedded. browse-url-button-regexp controls what's considered a button.

It can be set to a function that invokes an alternative browser.

Also, shell-strip-ctrl-m is declared obsolete.

This feature caused problems when '&&' was present in the previous command. Since this command emulates 'M-.' in Bash and zsh, neither of which treats '&' specially, the feature was removed for compatibility with these shells.

By default, invoking 'C-c .' with a numeric argument N would copy the Nth argument, counting from the first one. But if the new user option comint-insert-previous-argument-from-end is non-nil, it will copy the Nth argument counting from the last one. Thus 'C-c .' can now better emulate 'M-.' in both Bash and zsh, since the former counts from the beginning of the arguments, while the latter counts from the end.

'C-u M-x comint-run' will prompt for the switches interactively.

This hook permits a derived mode to supply a password for the underlying command interpreter without prompting the user. For example, in sql-mode, the password for connecting to the database may be stored in the connection wallet and may be passed on the command line to start the SQL interpreter. This is a potential security flaw that could expose user's database passwords on the command line through the use of a process list (Bug#8427). With this hook, it is possible to not pass the password on the command line and wait for the program to prompt for the password. When it does so, the password can be supplied to the SQL interpreter without involving the user just as if it had been supplied on the command line.

SQL Mode now supports the ELPA 「sql-indent」 package for assisting sophisticated SQL indenting rules. Note, however, that SQL is not like other programming languages like C, Java, or Python where code is sparse and rules for formatting are fairly well established. Instead SQL is more like COBOL (from which it came) and code tends to be very dense and line ending decisions driven by syntax and line length considerations to make readable code. Experienced SQL developers may prefer to rely upon existing Emacs facilities for formatting code but the 「sql-indent」 package provides facilities to aid more casual SQL developers layout queries and complex expressions.

Database passwords can now by stored in NETRC or JSON data files that may optionally be encrypted. When establishing an interactive session with the database via sql-connect or a product specific function, like sql-mysql or sql-postgres, the password wallet will be searched for the password. The 「sql-product」, 「sql-server」, 「sql-database」, and the 「sql-username」 will be used to identify the appropriate authorization. This eliminates the discouraged practice of embedding database passwords in your Emacs initialization.

See the 「auth-source」 module for complete documentation on the file formats. By default, the wallet file is expected to be in the user-emacs-directory, named "sql-wallet" or ".sql-wallet", with ".json" (JSON) or no (NETRC) suffix. Both file formats can optionally be encrypted with GPG by adding an additional ".gpg" suffix.

emulator in line mode.

You should instead set properties on known diagnostic symbols, like ':error' and ':warning', as demonstrated in the Flymake manual.

Control whether Flymake starts checking the buffer on save.

This enables more efficient backends. See the docstring of 「flymake-diagnostic-functions」 or the Flymake manual for details.

use post-self-insert-hook to check on newline.

it can't find the config file.

package.el used to refuse to install a package without the so-called "footer line", which appears at the very end of the file:

;;; FILENAME ends here

package.el will now install packages without this line, but it will issue a warning. To avoid this warning, packages should keep the "footer line".

Note that versions of Emacs older than 27.1 will not only refuse to install packages without such a line – they will be unable to parse package data. It is therefore recommended to keep this line.

In previous Emacsen, t checked that all signatures are valid. Now t only checks that at least one signature is valid and the new 'all' value needs to be used if you want to enforce that all signatures are valid. This only affects packages with multiple signatures.

changed slightly: If a usable OpenPGP configuration can't be found (for instance, if gpg isn't installed), it now has the same meaning as nil.

Example use in auctex.el: '(defconst auctex-version (package-get-version))'

When package-quickstart is non-nil, package.el precomputes a big autoloads file so that activation of packages can be done much faster, which can speed up your startup significantly. It also causes user options like package-user-dir and package-load-list to be consulted when package-quickstart-refresh is run rather than at startup so you don't need to set them in your early init file.

A new function has been added which allows users to filter the packages list by name: package-menu-filter-by-name. By default, it is bound to '/ n'. Additionally, the function package-menu-filter-by-keyword has been renamed from package-menu-filter. Its keybinding has also been changed to '/ k' (from 'f'). To clear any of the two filters, the user can now call the package-menu-clear-filter function, bound to '/ /' by default.

Previously, 'g' invoked tabulated-list-revert which did not update the cached archive data. It is now bound to revert-buffer, which will update the data.

package-menu-refresh is an obsolete alias for revert-buffer.

holding down the Ctrl key pops up a menu of previously visited Info nodes where you can select a node to go back (like in browsers).

The 'file://' URLs in Info documents can now be followed by passing them to the browse-url function, like the other protocols: 'ftp', 'http', and 'https'. This allows having references to local HTML files, for example.

This command finds definitions of the identifier at the place of a mouse click event, and is intended to be bound to a mouse event.

Previously, setting 「xref-marker-ring-length」 would only take effect if set before xref.el was loaded.

where it was invoked.

It encapsulates the logic pertinent to showing the result of xref-find-definitions. The user can change it to customize its behavior and the display of results.

The search-type Xref commands (e.g. xref-find-references or project-find-regexp) now show the results buffer even when there is only one hit. This can be altered by changing 「xref-show-xrefs-function」.

A new command 「xref-revert-buffer」 is bound to 'g'.

Using it, the etags backend now honors tags-case-fold-search during identifier completion.

Invoking 「checkdoc-buffer」 with a non-nil TAKE-NOTES argument (interactively, with a prefix arg) will now spell-check the doc strings and report all the spelling mistakes.

This mode is based on Icomplete, and its name stands for "Fake Ido". The point of this mode is to be an ido-mode workalike, providing most of the functionality present in ido-mode that is not in Icomplete, which is much more compatible with all of Emacs's completion facilities.

This can be controlled by the new 「ecomplete-sort-predicate」 user option.

"~/.emacs.d/ecompleterc" by default. Of course it will still find it if you have it in "~/.ecompleterc".

which means that "git am" diffs are recognized everywhere.

bound to the '[' and ']' keys: 「gnus-summary-prev-unseen-article」 and 「gnus-summary-next-unseen-article」. These take you (respectively) to the previous unseen or next unseen article. (These are the ones that are marked with "." in the summary mode lines.)

'never' for never expunging messages, 'immediately' for immediately expunging deleted messages, and 「on-exit」 to expunge deleted articles when exiting the group's summary buffer. Setting 「nnimap-expunge」 to nil or t is still supported but not recommended, since it may result in Gnus expunging all messages that have been flagged as deleted by any IMAP client (rather than just those that have been deleted by Gnus).

See the "(elisp) Atomic Windows" node of the Elisp manual for details.

「combined-local-lapsed」, which will show both the time (in the local timezone) and the lapsed time.

The nnimap backend used to do this unconditionally to work around problems on old versions of MS-Windows. This is now done only for Windows XP and older.

This feature can be enabled by setting the new 「nnimap-use-namespaces」 server variable to non-nil.

Limit to articles with score "at or below" the SCORE argument rather than "at or above".

from 「gnus-score-find-favourite-words」.

has a search engine.

See the concept index in the Gnus manual for the 「match-list」 entry.

to 'resize', which means that large images will be resized instead of displayed with an external program by default.

can be used to attach the current article(s) to a pre-existing Message buffer, or create a new Message buffer with the article(s) attached.

scans the article buffer for URLs, and offers them to the user to open with browse-url.

This option controls whether and how to use Gnus search groups as 'path:' search terms to 'notmuch'.

(i.e., buttons from widget.el). This has now changed, and they are now buttons (from button.el), and commands like 'TAB' now search for buttons instead of widgets. There should be no user-visible changes, but out-of-tree code that relied on widgets being present might now fail.

This hook is called after strings have been inserted into the buffer, and is free to alter point and window configurations, as it's not called from inside a save-excursion, as opposed to 「erc-insert-post-hook」.

and its value has been changed to Duck Duck Go.

The user option to use instead to alter text to be sent is now 「erc-pre-send-functions」.

Open and close parenthesis and apostrophe are not considered valid nick characters anymore, matching the given grammar in RFC 2812 section 2.3.1. This enables correct matching and highlighting of nicks when they are surrounded by parentheses, like "(nick)", and when adjacent to an apostrophe, like "nick's".

which better handles surrounding pair of parentheses.

which is like 「erc-switch-to-buffer」, but opens the buffer in another window.

which is like 「erc-track-switch-buffer」, but opens the buffer in another window.

when to use cookies when fetching embedded images. The default is to use them when the images are from the same domain as the main HTML document.

Invoking the command with a prefix argument will cause it to create a new EWW buffer for the URL instead of reusing the default one.

when tab-bar-mode is enabled.

If this command is invoked with no URL at point, it now downloads the current page instead of signaling an error.

【C-u RET】 keystroke on a link), the link will be flashed with the new 「shr-selected-link」 face to give the user feedback that the command has been executed.

If set, shr will not render tags with attribute 'aria-hidden="true"'. This attribute is meant to tell screen readers to ignore a tag.

of browse-url-secondary-browser-function.

hfy-fallback-color-values and the variables 「hfy-fallback-color-map」 and 「hfy-rgb-txt-color-map」 have been renamed from names that used 'colour' instead of 'color'.

defining new cl-defmethod of 「smtpmail-try-auth-method」.

attempt when communicating with the SMTP server(s), the 「smtpmail-servers-requiring-authorization」 user option can be used.

error message from the SMTP server. The new 「smtpmail-retries」 user option says how many times to retry.

Can be controlled via the new user option 「footnote-align-to-fn-text」.

formats (e.g. "black" => "#000000" => "rgb(0, 0, 0)") has been added, bound to 'C-c C-f'.

when escaping text and in addition all numeric entities when unescaping text.

The maximum level is used by default; customize font-lock-maximum-decoration to tone down the decoration.

If non-nil, the default, buffers opened during pdbtracking session are killed when pdbtracking session is finished.

It sends the statement delimited by 「python-nav-beginning-of-statement」 and 「python-nav-end-of-statement」 to the inferior Python process.

where the variable or function appeared in Emacs.

For convenience, view-lossage now displays the last keystrokes and commands in the same format as the edit buffer of edit-last-kbd-macro. This makes it possible to copy the lines from the buffer generated by view-lossage to the "Edit Macro" buffer created by edit-last-kbd-macro, and to save the macro by 'C-c C-c'.

can now be searched via 【C-s】.

This means you can now easily filter several major modes, as well as a single mode.

and 【C-r】 (isearch-repeat-backward). With a prefix argument, these commands repeat the search for the specified occurrence of the search string. A negative argument repeats the search in the opposite direction. This makes possible also to use a prefix argument for 'M-s .' (isearch-forward-symbol-at-point) to find the next Nth symbol. Also a prefix argument is supported for isearch-yank-until-char, isearch-yank-word-or-char, isearch-yank-symbol-or-char.

is possible now with new commands isearch-beginning-of-buffer and isearch-end-of-buffer bound to 'M-s M-<' and 'M-s M->' in Isearch. With a numeric argument, they go to the Nth absolute occurrence counting from the beginning/end of the buffer. This complements 【C-s】/【C-r】 that searches for the next Nth relative occurrence with a numeric argument.

of matches in the Isearch prompt. User options lazy-count-prefix-format and lazy-count-suffix-format define the format of the current and the total number of matches in the prompt's prefix and suffix, respectively.

It is useful in combination with lazy-highlight-cleanup customized to nil to leave matches highlighted in the whole buffer after exiting isearch. Also when lazy-highlight-buffer prepares highlighting in the buffer, navigation through the matches without flickering is more smooth. lazy-highlight-buffer-max-at-a-time controls the number of matches to highlight in one iteration while processing the full buffer.

'C-M-z' invokes new function isearch-yank-until-char, which yanks everything from point up to but not including the specified character into the search string. This is especially useful for keyboard macros.

'C-M-w' in isearch changed from isearch-del-char to the new function isearch-yank-symbol-or-char. isearch-del-char is now bound to 'C-M-d'.

【M-s h l】 invokes highlight-lines-matching-regexp using the search string to highlight lines matching the search string. This is similar to the existing binding 【M-s h r】 (highlight-regexp) that highlights JUST the search string.

to extend the search string by yanking text that ends at the new position after moving point in the current buffer. 'shift' extends the search string by motion commands while holding down the shift key.

scrolling any distance off screen.

and case-sensitivity together with search strings in the search ring.

The table used to check for equivalence of characters is now built using the complete chain of unicode decompositions of a character, rather than stopping after one level, such that searching for e.g. "GREEK SMALL LETTER IOTA" will now also find "GREEK SMALL LETTER IOTA WITH OXIA".

foldings, 「char-fold-exclude」 to remove foldings from default decomposition, and 「char-fold-symmetric」 to search for any of an equivalence class of characters. For example, with a nil value of 「char-fold-symmetric」 you can search for "e" to find "é", but not vice versa. With a non-nil value you can search for either, for example, you can search for "é" to find "e".

Backtrace mode adds fontification and commands for changing the appearance of backtrace frames. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands.

now take a zero prefix analogously to the non-Edebug counterparts.

When setting breakpoints in Edebug, an overlay with these faces are placed over the point in question, depending on whether they are enabled or not.

This command allows you to disable a breakpoint temporarily. This is mainly useful with breakpoints that are conditional and would take some time to recreate.

To clear all breakpoints in the current form, the 'U' command in 「edebug-mode」, or 'M-x edebug-unset-breakpoints' can be used.

previously-set breakpoints. However, if the code has changed substantially, this may not be possible.

This command removes Edebug instrumentation from all functions that have been instrumented.

using the new variables 「edebug-behavior-alist」, 「edebug-after-instrumentation-function」 and 「edebug-new-definition-function」. Edebug's behavior can be changed globally or for individual definitions.

Backtrace mode adds fontification, links and commands for changing the appearance of backtrace frames. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands.

The binding of 'd' in Edebug's keymap is now 「edebug-pop-to-backtrace」 which replaces 「edebug-backtrace」. Consequently Edebug's backtrace windows now behave like those of the Lisp Debugger and of ERT, in that when they appear they will be the selected window.

The new 「backtrace-goto-source」 command, bound to 's', works in Edebug's backtraces on backtrace frames whose source code has been instrumented by Edebug.

the XTerm window title. This feature is experimental and is disabled by default.

that contains a list of ignored directories and files. Clicking on the button with ellipsis unhides it. The abbreviation can be disabled by the new user option 「grep-find-abbreviate」. The new command 「grep-find-toggle-abbreviation」 toggles it interactively.

less verbose by removing non-essential information.

Backtrace mode adds fontification and commands for changing the appearance of backtrace frames. See the node "(elisp) Backtraces" in the Elisp manual for documentation of the new mode and its commands.

dimensions, instead of always using 16 pixels. As a result, Tetris, Snake and Pong are better playable on HiDPI displays.

This is useful for games where lower scores are better, like time-based games.

styles as configured by the user option completion-styles.

The value should be a function that determines how to find the next buffer to be used by next-error and previous-error. The default is to use the last buffer that navigated to the current error.

It can be used to set any buffer as the next one to be used by next-error and previous-error.

This means that pressing 'C-M-SPACE' now selects the entire tree by default, and not just the opening element.

'pcomplete'. Its UI is slightly different but can be customized to behave similarly, example: Pcomplete's default cycling can be obtained with '(setq completion-cycle-threshold 5)'.

To restore the old behavior, use

(add-hook 'eshell-expand-input-functions #'eshell-expand-history-references)

「eshell-uniqify-list」.

Previously 'eshell/kill' would fail if provided a kill signal to send to the process. It now accepts signals specified either by name or by its number.

The files specified by 「eshell-history-file-name」 and 「eshell-last-dir-ring-file-name」 can include symlinks; these are now followed when Emacs writes the relevant history variables to the disk.

variable for remote shells. It still defaults to "/bin/sh".

This user option can now have the value 'erase' to force to erase the output buffer before execution of the command, even if the output goes to the current buffer. Additional values 「beg-last-out」, 「end-last-out」, and 「save-point」 control where to put point in the output buffer after inserting the shell-command output.

shell-command-set-point-after-cmd control how point is handled between two consecutive shell commands in the same output buffer.

available for output of asynchronous shell commands.

Customize the new user option shell-command-prompt-show-cwd to enable it.

The Pcomplete functionality can be obtained via completion-at-point instead, by adding 「pcomplete-completions-at-point」 to completion-at-point-functions.

「pcomplete-uniqify-list」.

To recover the previous behavior, set new user option 「pcmpl-gnu-makefile-includes」 to nil.

This is just like fundamental-mode, except that it hides passwords under a "**" display property. When the cursor moves to this text, the real password is revealed (via reveal-mode). The new authinfo-hidden user option can be used to control what to hide.

or NextCloud hosted files and directories.

storages via the 'rclone' program. This feature is experimental.

with different user credentials. Contrary to the "sudo" method, no session is run permanently in the background. This is for security reasons.

are obsoleted in GVFS.

from auth-source search are taken into account. This can be disabled by setting the user option 「tramp-completion-use-auth-sources」 to nil.

Tramp for some look-alike remote file names.

multi-hop file names must match the previous hop. Default host names are adjusted to the host name from the previous hop.

The underlying session is disabled when the timeout expires. This is for security reasons.

possible to configure the remote login shell. This avoids problems with remote hosts, where "/bin/sh" is a link to a shell which cooperates badly with Tramp.

They allow saving remote files somewhere else when the corresponding host is not reachable anymore.

Setting this option to an integer causes URLs displayed in Rcirc buffers to be truncated to that many characters.

Two new user options are provided for this: 「rcirc-default-part-reason」 and 「rcirc-default-quit-reason」.

names of buffers shown by the windows of a window configuration.

This is controlled by 「message-expand-name-standard-ui」. With the standard UI the different sources (ecomplete, bbdb, and eudc) are matched together and try to obey completion-styles. It should work for other completion front ends like Company.

This can be customized via the new user option 「message-cite-level-function」 and the new 'message-cited-text-*' faces.

when the PGP keyring contains a public key for every recipient. To achieve this, add 「message-sign-encrypt-if-all-keys-available」 to 「message-send-hook」.

'"foo@bar.com" <foo@bar.com>', Message will elide the repeated "name" from the address field in the response.

as it has been reported that many recipients can't read forwards that are formatted as MIME digests.

exclude most headers when forwarding.

When 「mml-secure-openpgp-sign-with-sender」 is non-nil, message sender's email address (in addition to its old behavior) will also be used to set gpg's "–sender email@domain" option.

The option is useful for two reasons when verifying the signature:

1. GnuPG's TOFU statistics are updated for the specific user id (email) only. See gpg(1) man page about "–sender".
2. GnuPG's "–auto-key-retrieve" functionality can use WKD (web key directory) method for finding the signer's key. You need GnuPG 2.2.17 to fully benefit from this feature. See gpg(1) man page for "–auto-key-retrieve".

According to RFC 5322, only the 'angles' value is valid.

It now applies to epg functions as well as epa functions.

'epa–decode-coding-string', and 'epa–select-safe-coding-system' have been removed. Use encode-coding-string, decode-coding-string, and select-safe-coding-system instead.

The value of the new 'sender' slot (if a string) is used to set gpg's "–sender" option. This feature is used by 「mml-secure-openpgp-sign-with-sender」. See gpg(1) manual page about "–sender" for more information.

Previously, it found these versions by mistake. The intent was to find GnuPG 2.1.6 or later, or find GnuPG 1.4.3 or later within the GnuPG 1 series.

If this option is non-nil, messages appended to an output file by the rmail-output command have their Deleted flag reset.

selects the messages to summarize with a regexp that matches the sender of the current message.

This is handy in Lisp programs that run on a non-main thread and want to signal the main thread, e.g., when they encounter an error.

Instead, error messages are just printed in the main thread.

See the current list of live threads in a tabulated-list buffer which automatically updates. In the buffer, you can use 's q' or 's e' to signal a thread with quit or error respectively, or get a snapshot backtrace with 'b'.

A symbol 'uuid' can be passed to thing-at-point and it returns the UUID at point.

and return them as numbers.

Just like thing-at-point itself.

The new command accepts a prefix numeric argument to choose the subexpression.

When there is no menu for a mode, display the mode name after the indicator instead of just the indicator (which is sometimes cryptic).

when given in a string. Previously, '(any "\x80-\xff")' would match characters U+0080…U+00FF. Now the expression matches raw bytes in the 128…255 range, as expected.

'(or)' produces a regexp that never matches anything, while '(seq)' matches the empty string, each being an identity for the operation. This also works for their aliases: '|' for 'or'; ':', 'and' and 'sequence' for 'seq'. The symbol 'unmatchable' can be used as an alternative to '(or)'.

In this case, 'rx' will generate code which produces a regexp string at run time, instead of a constant string.

These macros add new forms to the rx notation.

Both match any single character; 'anychar' is more descriptive.

With 'or' and 'not', it can be used to compose character-matching expressions from simpler parts.

The argument can now also be a character, a single-character string, an 'intersection' form, or an 'or' form whose arguments each match a single character.

For example, '(or (or "IN" "OUT") (or "INPUT" "OUTPUT"))' now matches the whole string "INPUT" if present, not just "IN". Previously, this was only guaranteed inside a single 'or' form of string literals.

This allows creating and immediately parenting a minibuffer-only child frame when making a frame.

These predicates are to be preferred over display-graphic-p when testing for blinking cursor capability and the capability to have symbols (e.g., '[return]', '[tab]', '[backspace]') as keys respectively.

You can now customize which sorting indicator character to display near the current column in Tabulated Lists (see user options tabulated-list-gui-sort-indicator-asc, tabulated-list-gui-sort-indicator-desc, tabulated-list-tty-sort-indicator-asc, and tabulated-list-tty-sort-indicator-desc).

list mode: 'w' (which widens the current column) and 'c' which makes the current column contract.

This function clears all tags from the padding area in the current buffer. Tags are typically added by calling tabulated-list-put-tag.

This user option allows for the customization of the modifier key used in a terminal frame.

If a file imports Facebook's 'React' library, or if the file uses the extension ".jsx", then various features supporting XML-like syntax will be supported in js-mode and derivative modes. (js-jsx-mode no longer needs to be enabled.)

This is turned on by default.

This is off by default.

Previously, JSX indentation usually only worked when an element was wrapped in parenthesis (e.g. in a 'return' statement or a function call). It would also fail in many intricate cases. Now, indentation should work anywhere without parenthesis; many more intricacies are supported; and, indentation conventions align more closely with those of the React developer community (see 'js-jsx-align->-with-<'), otherwise still adhering to SGML conventions.

Commonly in JSX code, a '>' on its own line is indented at the same level as its opening '<'. This is the new default for JSX. This behavior is slightly different than that used by SGML in Emacs, where '>' is indented at the same level as attributes, which was also the old default for JSX.

This is turned on by default. To get back the old default indentation behavior of aligning '>' with attributes, set 'js-jsx-align->-with-<' to nil.

Since JSX is a syntax extension of JavaScript, it makes the most sense for JSX expressions to be indented the same number of spaces as other JS expressions. This is a breaking change, but it probably aligns with how you'd expect this indentation to behave. If you want JSX to be indented like JS, you won't need to change your config.

The old behavior can be emulated by controlling JSX indentation independently of JS, by setting js-jsx-indent-level.

If you wish to indent JSX by a different number of spaces than JS, set this user option to the desired number.

Previously, the mode name was simply 'JavaScript'. Now, when a syntax extension like JSX is enabled, the mode name is 'JavaScript[JSX]'. Set this variable to nil to disable the new behavior.

Packages deriving from js-mode with define-derived-mode should call this function to add enabled syntax extensions to their mode name, too.

When set to a non-nil value, buffers in Auto Revert mode are no longer polled for changes periodically. This reduces the power consumption of an idle Emacs, but may fail on some network file systems; set auto-revert-notify-exclude-dir-regexp to match files where notification is not supported. The default value is nil.

A major mode can declare that notification on the buffer's default directory is sufficient to know when updates are required, by setting the new variable buffer-auto-revert-by-notification to a non-nil value. Auto Revert mode can use this information to avoid polling the buffer periodically when auto-revert-avoid-polling is non-nil.

function that can be used for more fine-grained control of which buffers to auto-revert.

Allows setting the path to the password-store, defaults to "~/.password-store".

Specifies separator between host and port, defaults to colon ":".

This makes the package usable with physical tokens requiring touching a sensor for every decryption.

aliases of bookmark-default-file.

When non-nil, watch whether the bookmark file has changed on disk.

This bookmark file format has not been used in Emacs since at least version 19.34, released in 1996, and will no longer be automatically converted to the new bookmark file format.

The following functions are now declared obsolete: bookmark-grok-file-format-version, bookmark-maybe-upgrade-file-format, bookmark-upgrade-file-format-from-0, and bookmark-upgrade-version-0-alist.

This runs after changing the dictionary and could be used to automatically spellcheck a buffer when changing language without needing to advice ispell-change-dictionary.

This command is bound to 「S-down」 and scrolls the buffer up in particular when the end of the buffer is visible in the window.

Use mouse-wheel-mode instead. Note that mouse-wheel-mode is already enabled by default on most graphical displays.

The previously used timestamp format of a list of integers is still supported, but is deprecated. The default value has not changed.

This results in the use of Gravatar's default size of 80 pixels.

This is possible using the new user options 「gravatar-default-image」 and 「gravatar-force-default」.

good replacement, even in very large source files.

Specifying '%5z' in 「time-stamp-format」 or 「time-stamp-pattern」 expands to the time zone offset, e.g., '+0100'. The time zone used is specified by 「time-stamp-time-zone」.

Because this feature is new in Emacs 27.1, do not use it in the local variables section of any file that might be edited by an older version of Emacs.

The new documented/recommended %-conversions are closer to those used by format-time-string and are compatible at least as far back as Emacs 22.1 (released in 2007).

Uppercase abbreviated day name of week: was %3A, now %#a Full day name of week: was %:a, now %:A Uppercase abbreviated month name: was %3B, now %#b Full month name: was %:b, now %:B Four-digit year: was %:y, now %Y Lowercase timezone name: was %z, now %#Z Fully-qualified host name: was %s, now %Q Unqualified host name: (was none), now %q Login name: was %u, now %l User's full name: was %U, now %L

Merely having '(add-hook 'before-save-hook #'time-stamp)' in your Emacs init file does not expose you to this change. However, if you set 「time-stamp-format」 or 「time-stamp-pattern」 with a file-local variable, you may need to update the value.

To do this, use 'c-toggle-comment-style', if needed, to set the desired default comment style (block or line); then set the user option 'c-mark-wrong-style-of-comment' to non-nil.

It's a simple convenience function for looking up MIME types based on file name extensions.

types is sorted and chosen has changed. Earlier, the most specific viewer was chosen, even if there was a general override in "~/.mailcap". For instance, if "etc/mailcap" has an entry for "image/gif", that one will be chosen even if you have an entry for "image/*" in your "~.mailcap" file. But with the new method, entries from "~/.mailcap" overrides all system and Emacs-provided defaults. To get the old method back, set mailcap-prefer-mailcap-viewers to nil.

Functions that want to affect the message text (for example, to change highlighting) can no longer use 「mh-show-mode-hook」, because the message contents will not yet have been inserted when the hook is called. Such functions should now be attached to 「mh-show-hook」.

directories if you ask it for a "file:///dir" URL. Since this is a low-level library, such decisions (if they are to be made at all) are left to higher-level functions.

The new command tab-bar-mode enables the tab bar at the top of each frame (including TTY frames), where you can use tabs to switch between named persistent window configurations.

The 【C-x t】 sequence is the new prefix key for tab-related commands: 【C-x t 2】 creates a new tab; 【C-x t 0】 deletes the current tab; 【C-x t b】 switches to buffer in another tab; 【C-x t f】 and 'C-x t C-f' edit file in another tab; and 【C-TAB】 and 'S-C-TAB' switch to the next or previous tab. You can also switch between tabs and create/delete tabs with a mouse.

Tab-related commands are available even when tab-bar-mode is disabled: by default, they enable tab-bar-mode in that case.

The X resource "tabBar", class "TabBar" enables the tab bar when its value is "on", "yes" or "1".

The user option tab-bar-position specifies where to show the tab bar.

Tab-related commands can be used even without the tab bar when tab-bar-mode is disabled by a nil value of the user option tab-bar-show. Without the tab bar you can switch between tabs using completion on tab names, or using tab-switcher.

Read the new Info node "(emacs) Tab Bars" for full description of all related features.

The new command global-tab-line-mode enables the tab line above each window, which you can use to switch buffers in the window. Selecting the previous window-local tab is the same as typing 'C-x <LEFT>' (previous-buffer), selecting the next tab is the same as 'C-x <RIGHT>' (next-buffer). Both commands support a numeric prefix argument as a repeat count. Clicking on the plus icon adds a new buffer to the window-local tab line of buffers. Using the mouse wheel on the tab line scrolls tabs.

Read the new Info node "(emacs) Tab Line" for full description of all related features.

timestamps of various forms, including a new timestamp form '(TICKS . HZ)' where TICKS is an integer and HZ a positive integer denoting a clock frequency.

it is planned to change in a future Emacs version, to exploit bignums. The documentation has been updated to mention that the timestamp format may change and that programs should use functions like format-time-string, decode-time, and time-convert rather than probing the innards of a timestamp directly, or creating a timestamp by hand.

This affects decode-time, which generates these timestamps, as well as functions like encode-time that accept them. The subsecond info is present as a '(TICKS . HZ)' value in the seconds element of a decoded timestamp, and decode-time has a new optional FORM argument specifying the form of the seconds member. For example, if X is the timestamp '(1566009571321878186 . 1000000000)', which represents "2019-08-17 02:39:31.321878186 UTC", '(decode-time X t t)' returns '((31321878186 . 1000000000) 39 2 17 8 2019 6 nil 0)' instead of the traditional '(31 39 2 17 8 2019 6 nil 0)' returned by plain '(decode-time X t)'. Although the default FORM is currently 'integer', which truncates the seconds to an integer and is the traditional behavior, this default may change in future Emacs versions, so callers requiring an integer should specify FORM explicitly.

The old encode-time API is still supported.

intervals has been added. The main function to use is 「iso8601-parse」, but there's also 「iso8601-parse-date」, 「iso8601-parse-time」, 「iso8601-parse-duration」 and 「iso8601-parse-interval」. All these functions return decoded time structures, except the final one, which returns three of them (start, end and duration).

infinities and NaNs too, and propagate them or return nil like floating-point operators do. If both arguments are finite, these functions now return exact results instead of rounding in some cases, and they also avoid excess precision when that is easy.

that acts like the '0' flag but also puts a '+' before nonnegative years containing more than four digits. This is for compatibility with POSIX.1-2017.

decoded-time-second, decoded-time-minute, decoded-time-hour, decoded-time-day, decoded-time-month, decoded-time-year, decoded-time-weekday, decoded-time-dst and decoded-time-zone accessors can be used.

days there are in a month in a specific year), date-ordinal-to-time (that computes the date of an ordinal day), decoded-time-add (for doing computations on a decoded time structure), make-decoded-time (for making a decoded time structure with only the given keywords filled out), and decoded-time-set-defaults (which fills in nil elements as if it's midnight January 1st, 1970) have been added.

if it is not known whether daylight saving time is in effect. Formerly they were inconsistent: encode-time returned t in this situation, whereas parse-time-string returned nil. Now they consistently use nil to mean that DST is not in effect, and use -1 to mean that it is not known whether DST is in effect.

according to the given numeric value.

An Exif library has been added that can parse JPEG files and output data about creation times and orientation and the like. exif-parse-file and exif-parse-buffer are the main interface functions.

according to the orientation in the Exif data, if any.

With a prefix argument, image-rotate now rotates the image at point 90 degrees counter-clockwise, instead of the default clockwise.

By default, the image will resize upon first display and whenever the window's dimensions change. Two user options image-auto-resize and image-auto-resize-on-window-resize control the resizing behavior (including the possibility to disable auto-resizing). A new prefix key 's' contains the commands that can be used to fit the image to the window manually.

The image parameters image-transform-rotation, image-transform-scale and image-transform-resize are now declared buffer-local, so each buffer could have its own values for these parameters.

the file in the dired buffer(s) for the directory the file is in; 'u', which unmarks the file; and 'w', which pushes the current buffer's file name to the kill ring.

If you need to view exotic image formats for which Emacs doesn't have native support, customize the new user option image-use-external-converter to t. If your system has GraphicsMagick, ImageMagick or 'ffmpeg' installed, they will then be used to convert images automatically before displaying them.

supported by the external image converters, like WEPB, BMP and ICO. These now default to using image-mode.

image-mode started using ImageMagick by default for all images some years back. It now respects imagemagick-types-inhibit as a way to disable that.

Specifically, it puts the module name into load-history, prints loading messages if requested, and protects against recursive loads.

input while module code is running.

convert between timespec structures and Emacs Lisp time values.

'extract_biginteger' to create and extract arbitrary-size integer values.

to the major version of the latest Emacs supported by the header.