Eshell is a shell-like command interpreter implemented in Emacs Lisp.
It invokes no external processes except for those requested by the
user. It is intended to be an alternative to the IELM (see Emacs Lisp Interaction in The Emacs Editor)
REPL for Emacs and with an interface similar to command shells
such as bash, zsh, rc, or
4dos.
This manual is for Eshell, the Emacs shell.
Copyright © 1999–2022 Free Software Foundation, Inc.
Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with the Front-Cover Texts being “A GNU Manual”, and with the Back-Cover Texts as in (a) below. A copy of the license is included in the section entitled “GNU Free Documentation License”.
(a) The FSF’s Back-Cover Text is: “You have the freedom to copy and modify this GNU manual.”
Eshell is a command shell written in Emacs Lisp. Everything it does, it uses Emacs’s facilities to do. This means that Eshell is as portable as Emacs itself. It also means that cooperation with Lisp code is natural and seamless.
What is a command shell? To properly understand the role of a shell, it’s necessary to visualize what a computer does for you. Basically, a computer is a tool; in order to use that tool, you must tell it what to do—or give it “commands.” These commands take many forms, such as clicking with a mouse on certain parts of the screen. But that is only one form of command input.
By far the most versatile way to express what you want the computer to do is by using an abbreviated language called script. In script, instead of telling the computer, “list my files, please”, one writes a standard abbreviated command word—‘ls’. Typing ‘ls’ in a command shell is a script way of telling the computer to list your files.1
The real flexibility of this approach is apparent only when you realize that there are many, many different ways to list files. Perhaps you want them sorted by name, sorted by date, in reverse order, or grouped by type. Most graphical browsers have simple ways to express this. But what about showing only a few files, or only files that meet a certain criteria? In very complex and specific situations, the request becomes too difficult to express using a mouse or pointing device. It is just these kinds of requests that are easily solved using a command shell.
For example, what if you want to list every Word file on your hard drive, larger than 100 kilobytes in size, and which hasn’t been looked at in over six months? That is a good candidate list for deletion, when you go to clean up your hard drive. But have you ever tried asking your computer for such a list? There is no way to do it! At least, not without using a command shell.
The role of a command shell is to give you more control over what your computer does for you. Not everyone needs this amount of control, and it does come at a cost: Learning the necessary script commands to express what you want done. A complicated query, such as the example above, takes time to learn. But if you find yourself using your computer frequently enough, it is more than worthwhile in the long run. Any tool you use often deserves the time spent learning to master it. 2
Contributions to Eshell are welcome. I have limited time to work on this project, but I will gladly add any code you contribute to me to this package.
The following persons have made contributions to Eshell.
Apart from these, a lot of people have sent suggestions, ideas, requests, bug reports and encouragement. Thanks a lot! Without you there would be no new releases of Eshell.
In a command shell, everything is done by invoking commands. This chapter covers command invocations in Eshell, including the command history and invoking commands in a script file.
Unlike regular system shells, Eshell never invokes kernel functions
directly, such as exec(3). Instead, it uses the Lisp functions
available in the Emacs Lisp library. It does this by transforming the
input line into a callable Lisp form.3
The command can be either an Elisp function or an external command. Eshell looks first for an alias (see Aliases) with the same name as the command, then a built-in (see Built-in commands) or a function with the same name; if there is no match, it then tries to execute it as an external command.
The semicolon (;) can be used to separate multiple command
invocations on a single line. A command invocation followed by an
ampersand (&) will be run in the background. Eshell has no job
control, so you can not suspend or background the current process, or
bring a background process into the foreground. That said, background
processes invoked from Eshell can be controlled the same way as any
other background process in Emacs.
Command arguments are passed to the functions as either strings or
numbers, depending on what the parser thinks they look like. If you
need to use a function that takes some other data type, you will need to
call it in an Elisp expression (which can also be used with
expansions). As with other shells, you can
escape special characters and spaces with the backslash (\) and
apostrophes ('') and double quotes (""). This is needed
especially for file names with special characters like pipe
(|), which could be part of remote file names.
Several commands are built-in in Eshell. In order to call the
external variant of a built-in command foo, you could call
*foo. Usually, this should not be necessary. You can check
what will be applied by the which command:
~ $ which ls eshell/ls is a compiled Lisp function in `em-ls.el' ~ $ which *ls /bin/ls
If you want to discard a given built-in command, you could declare an alias (see Aliases). Example:
~ $ which sudo eshell/sudo is a compiled Lisp function in `em-tramp.el'. ~ $ alias sudo '*sudo $*' ~ $ which sudo sudo is an alias, defined as "*sudo $*"
If you would prefer to use the built-in commands instead of the external
commands, set eshell-prefer-lisp-functions to t.
Some of the built-in commands have different behavior from their
external counterparts, and some have no external counterpart. Most of
these will print a usage message when given the --help option.
addpath ¶Adds a given path or set of paths to the PATH environment variable, or, with no arguments, prints the current paths in this variable.
alias ¶Define an alias (see Aliases). This adds it to the aliases file.
clear ¶Scrolls the contents of the eshell window out of sight, leaving a blank window. If provided with an optional non-nil argument, the scrollback contents are cleared instead.
date ¶Similar to, but slightly different from, the GNU Coreutils
date command.
define ¶Define a varalias. See Variable Aliases in The Emacs Lisp Reference Manual.
diff ¶Use Emacs’s internal diff (not to be confused with
ediff). See Comparing Files in The GNU Emacs Manual.
grep ¶agrepegrepfgrepglimpseThe grep commands are compatible with GNU grep, but
use Emacs’s internal grep instead.
info ¶Same as the external info command, but uses Emacs’s internal
Info reader.
jobs ¶List subprocesses of the Emacs process, if any, using the function
list-processes.
kill ¶Kill processes. Takes a PID or a process object and an optional signal specifier which can either be a number or a signal name.
listify ¶Eshell version of list. Allows you to create a list using Eshell
syntax, rather than Elisp syntax. For example, ‘listify foo bar’
and ("foo" "bar") both evaluate to ("foo" "bar").
locate ¶Alias to Emacs’s locate function, which simply runs the external
locate command and parses the results.
See Dired and Find in The GNU Emacs Manual.
make ¶Run make through compile when run asynchronously
(e.g., ‘make &’). See Compilation in The GNU Emacs
Manual. Otherwise call the external make command.
occur ¶Alias to Emacs’s occur.
See Other Repeating Search in The GNU Emacs Manual.
printnl ¶Print the arguments separated by newlines.
cd ¶This command changes the current working directory. Usually, it is
invoked as ‘cd foo’ where foo is the new working directory.
But cd knows about a few special arguments:
When it receives no argument at all, it changes to the home directory.
Giving the command ‘cd -’ changes back to the previous working directory (this is the same as ‘cd $-’).
The command ‘cd =’ shows the directory stack. Each line is numbered.
With ‘cd =foo’, Eshell searches the directory stack for a directory matching the regular expression ‘foo’ and changes to that directory.
With ‘cd -42’, you can access the directory stack by number.
su ¶sudoUses TRAMP’s su or sudo method see (tramp)Inline methods
to run a command via su or sudo. These commands
are in the eshell-tramp module, which is disabled by default.
Eshell knows a few built-in variables:
$+ ¶This variable always contains the current working directory.
$- ¶This variable always contains the previous working directory (the
current working directory from before the last cd command).
$_ ¶It refers to the last argument of the last command.
$$ ¶This is the result of the last command. In case of an external
command, it is t or nil.
$? ¶This variable contains the exit code of the last command (0 or 1 for Lisp functions, based on successful completion).
See Aliases, for the built-in variables ‘$*’, ‘$1’, ‘$2’, …, in alias definitions.
Since Eshell is just an Emacs REPL4, it
does not have its own scope, and simply stores variables the same you
would in an Elisp program. Eshell provides a command version of
setq for convenience.
Aliases are commands that expand to a longer input line. For example,
ll is a common alias for ls -l, and would be defined
with the command invocation alias ll 'ls -l $*'; with this defined,
running ‘ll foo’ in Eshell will actually run ‘ls -l foo’.
Aliases defined (or deleted) by the alias command are
automatically written to the file named by eshell-aliases-file,
which you can also edit directly (although you will have to manually
reload it).
Note that unlike aliases in Bash, arguments must be handled explicitly. Typically the alias definition would end in ‘$*’ to pass all arguments along. More selective use of arguments via ‘$1’, ‘$2’, etc., is also possible. For example, alias mcd 'mkdir $1 && cd $1' would cause mcd foo to create and switch to a directory called ‘foo’.
The ‘history’ command shows all commands kept in the history ring
as numbered list. If the history ring contains
eshell-history-size commands, those numbers change after every
command invocation, therefore the ‘history’ command shall be
applied before using the expansion mechanism with history numbers.
The n-th entry of the history ring can be applied with the ‘!n’
command. If n is negative, the entry is counted from the end
of the history ring.
When history event designators are enabled (by adding
eshell-expand-history-references to
eshell-expand-input-functions), ‘!foo’ expands to the last
command beginning with foo, and ‘!?foo’ to the last
command containing foo. The n-th argument of the last command
beginning with foo is accessible by !foo:n.
The history ring is loaded from a file at the start of every session,
and written back to the file at the end of every session. The file path
is specified in eshell-history-file-name. Unlike other shells,
such as Bash, Eshell can not be configured to keep a history ring of a
different size than that of the history file.
Since the default buffer navigation and searching key-bindings are still present in the Eshell buffer, the commands for history navigation and searching are bound to different keys:
History I-search.
Previous and next history line. If there is anything on the input line when you run these commands, they will instead jump to the previous or next line that begins with that string.
Eshell uses the pcomplete package for programmable completion, similar
to that of other command shells. Argument completion differs depending
on the preceding command: for example, possible completions for
rmdir are only directories, while rm completions can
be directories and files. Eshell provides predefined completions
for the built-in functions and some common external commands, and you
can define your own for any command.
Eshell completion also works for lisp forms and glob patterns. If the point is
on a lisp form, then TAB will behave similarly to completion in
elisp-mode and lisp-interaction-mode. For glob patterns, the
pattern will be removed from the input line, and replaced by the
completion.
If you want to see the entire list of possible completions (e.g. when it’s
below the completion-cycle-threshold), press M-?.
Pcomplete, short for programmable completion, is the completion library originally written for Eshell, but usable for command completion5 in other modes.
Completions are defined as functions (with defun) named
pcomplete/COMMAND, where COMMAND is the name of the
command for which this function provides completions; you can also name
the function pcomplete/MAJOR-MODE/COMMAND to define completions
for a specific major mode.
for loopBecause Eshell commands can not (easily) be combined with lisp forms,
Eshell provides a command-oriented for-loop for convenience.
The syntax is as follows:
for VAR in TOKENS { command invocation(s) }
where ‘TOKENS’ is a space-separated sequence of values of VAR for each iteration. This can even be the output of a command if ‘TOKENS’ is replaced with ‘{ command invocation }’.
You can run Eshell scripts much like scripts for other shells; the main
difference is that since Eshell is not a system command, you have to run
it from within Emacs. An Eshell script is simply a file containing a
sequence of commands, as with almost any other shell script. Scripts
are invoked from Eshell with source, or from anywhere in Emacs
with eshell-source-file.
If you wish to load a script into your current environment,
rather than in a subshell, use the . command.
Expansion in a command shell is somewhat like macro expansion in macro
parsers (such as cpp and m4), but in a command
shell, they are less often used for constants, and usually for using
variables and string manipulation.6 For example, $var on a line
expands to the value of the variable var when the line is
executed. Expansions are usually passed as arguments, but may also be
used as commands.7
Eshell has different $ expansion syntax from other shells. There
are some similarities, but don’t let these lull you into a false sense
of familiarity.
$varExpands to the value bound to var. This is the main way to use variables in command invocations.
$"var"$'var'Expands to the value bound to var. This is useful to disambiguate the variable name when concatenating it with another value, such as ‘$"var"-suffix’.
$#varExpands to the length of the value bound to var. Raises an error if the value is not a sequence (see Sequences in The Emacs Lisp Reference Manual).
$(lisp)Expands to the result of evaluating the S-expression (lisp). On
its own, this is identical to just (lisp), but with the $,
it can be used in a string, such as ‘/some/path/$(lisp).txt’.
${command}Returns the output of command, which can be any valid Eshell
command invocation, and may even contain expansions.
$<command>As with ‘${command}’, evaluates the Eshell command invocation
command, but writes the output to a temporary file and
returns the file name.
$var[i]Expands to the ith element of the value bound to var. If
the value is a string, it will be split at whitespace to make it a list.
Again, raises an error if the value is not a sequence.
$var[: i]As above, but now splitting occurs at the colon character.
$var[: i j]As above, but instead of returning just a string, it now returns a list of two strings. If the result is being interpolated into a larger string, this list will be flattened into one big string, with each element separated by a space.
$var["\\\\" i]Separate on backslash characters. Actually, the first argument – if it doesn’t have the form of a number, or a plain variable name – can be any regular expression. So to split on numbers, use ‘$var["[0-9]+" 10 20]’.
$var[hello]Calls assoc on var with "hello", expecting it to be
an alist (see Association Lists in The Emacs Lisp Reference Manual).
$#var[hello]Returns the length of the cdr of the element of var whose
car is equal to "hello".
Eshell’s globbing syntax is very similar to that of Zsh. Users coming from Bash can still use Bash-style globbing, as there are no incompatibilities. Most globbing is pattern-based expansion, but there is also predicate-based expansion. See Filename Generation in The Z Shell Manual, for full syntax. To customize the syntax and behavior of globbing in Eshell see the Customize8 groups “eshell-glob” and “eshell-pred”.
Since Eshell does not communicate with a terminal like most command shells, IO is a little different.
If you try to run programs from within Eshell that are not line-oriented, such as programs that use ncurses, you will just get garbage output, since the Eshell buffer is not a terminal emulator. Eshell solves this problem by running such programs in Emacs’s terminal emulator.
Programs that need a terminal to display output properly are referred
to in this manual as “visual commands”, because they are not simply
line-oriented. You must tell Eshell which commands are visual, by
adding them to eshell-visual-commands; for commands that are
visual for only certain sub-commands – e.g., ‘git log’ but
not ‘git status’ – use eshell-visual-subcommands; and for
commands that are visual only when passed certain options, use
eshell-visual-options.
Caution: Some tools such as Git use the pager ‘less’ by default to paginate their output but call it with its ‘-F’ option. This option causes ‘less’ to echo the output instead of paginating it if the output is less than one page long. This causes undesirable behavior if, e.g., ‘git diff’, is defined as a visual subcommand. It’ll work if the output is big enough and fail if it is less than one page long. If that occurs to you, search for configuration options for calling ‘less’ without the ‘-F’ option. For Git, you can do that using ‘git config --global core.pager 'less -+F'’.
If you want the buffers created by visual programs killed when the
program exits, customize the variable
eshell-destroy-buffer-when-process-dies to a non-nil
value; the default is nil.
Redirection is mostly the same in Eshell as it is in other command
shells. The output redirection operators > and >> as
well as pipes are supported, but there is not yet any support for
input redirection. Output can also be redirected to buffers, using
the >>> redirection operator, and Elisp functions, using
virtual devices.
The buffer redirection operator, >>>, expects a buffer object
on the right-hand side, into which it inserts the output of the
left-hand side. e.g., ‘echo hello >>> #<buffer *scratch*>’
inserts the string "hello" into the *scratch* buffer.
The convenience shorthand variant ‘#<buffer-name>’, as in
‘#<*scratch*>’, is also accepted.
eshell-virtual-targets is a list of mappings of virtual device
names to functions. Eshell comes with two virtual devices:
/dev/kill, which sends the text to the kill ring, and
/dev/clip, which sends text to the clipboard.
You can, of course, define your own virtual targets. They are defined
by adding a list of the form ‘("/dev/name" function mode)’ to
eshell-virtual-targets. The first element is the device name;
function may be either a lambda or a function name. If
mode is nil, then the function is the output function; if it is
non-nil, then the function is passed the redirection mode as a
symbol–overwrite for >, append for >>, or
insert for >>>–and the function is expected to return
the output function.
The output function is called once on each line of output until
nil is passed, indicating end of output.
Eshell provides a facility for defining extension modules so that they
can be disabled and enabled without having to unload and reload them,
and to provide a common parent Customize group for the
modules.9 An Eshell
module is defined the same as any other library but one requirement: the
module must define a Customize10
group using eshell-defgroup (in place of defgroup) with
eshell-module as the parent group.11 You also need to load the following as shown:
(eval-when-compile (require 'cl-lib) (require 'esh-mode) (require 'eshell)) (require 'esh-util)
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If you find a bug or misfeature, don’t hesitate to report it, by using M-x report-emacs-bug. The same applies to feature requests. It is best to discuss one thing at a time. If you find several unrelated bugs, please report them separately.
Below is a list of some known problems with Eshell version 2.4.2, which is the version included with Emacs 22.
Allow for a Bash-compatible syntax, such as:
alias arg=blah
function arg () { blah $* }
In fact, piping to a process from a looping construct doesn’t work in
general. If I change the call to eshell-copy-handles in
eshell-rewrite-for-command to use eshell-protect, it seems
to work, but the output occurs after the prompt is displayed. The whole
structured command thing is too complicated at present.
You press TAB, but no completions appear, even though the directory has matching files. This behavior is rare.
This happens because the grep Lisp function returns immediately,
and then the asynchronous grep process expects to examine the
temporary file, which has since been deleted.
If the text before point reads "./run", and you type C-r r u n, it will repeat the line for every character typed.
Hitting space during a process invocation, such as make, will
cause it to track the bottom of the output; but backspace no longer
scrolls back.
unload-feature EshellThis happened a few times in Emacs 21, but has been irreproducible since.
sleep-for when killing child processesMake it so that the Lisp command on the right of the pipe is repeatedly
called with the input strings as arguments. This will require changing
eshell-do-pipelines to handle non-process targets.
See the above entry.
less without arguments on WindowsThe result in the Eshell buffer is:
Spawning child process: invalid argument
Also a new less buffer was created with nothing in it…
(presumably this holds the output of less).
If less.exe is invoked from the Eshell command line, the
expected output is written to the buffer.
Note that this happens on NT-Emacs 20.6.1 on Windows 2000. The term.el
package and the supplied shell both use the cmdproxy program
for running shells.
cpThis is because the tar option –remove-files doesn’t do so. Should it be Eshell’s job?
standard-output and standard-errorThis would be so that if a Lisp function calls print, everything
will happen as it should (albeit slowly).
So that M-DEL acts in a predictable manner, etc.
If a script file, somewhere in the middle, uses ‘> /dev/null’, output from all subsequent commands is swallowed.
Make it similar to the way that esh-arg.el is structured. Then add parsing of ‘$[?\n]’.
/usr/local/src/editors/vim $ vi **/CVS(/)/Root(.) Invalid regexp:
"Unmatched ( or \\("
With zsh, the glob above expands to all files named
Root in directories named CVS.
Perhaps it should interpolate all permutations, and make that the
globbing result, since otherwise hitting return here will result in
“(list of filenames)/bin”, which is never valuable. Thus, one could
cat only C backup files by using ‘ls ${identity *.c}~’.
In that case, having an alias command name glob for
identity would be useful.
umask, implement chmod in Lispeshell-expand-file-nameThis would use a data table to transform things such as ‘~+’, ‘...’, etc.
It only really needs: to be hooked onto the output filter and the pre-command hook, and to have the input-end and input-start markers. And to know whether the last output group was “successful.”
This would include: variables, history, buffer, input, dir stack, etc.
It means that files beginning with a dot should be included in the glob match.
At the moment, this is not supported.
An error should be generated only if eshell-error-if-no-glob is
non-nil.
indent-according-to-mode to occureshell-auto-accumulate-listThis is a list of commands for which, if the user presses RET, the text is staged as the next Eshell command, rather than being sent to the current interactive process.
wait doesn’t work with process ids at the momentWith smart display active, if RET is held down, after a while it can’t keep up anymore and starts outputting blank lines. It only happens if an asynchronous process is involved…
I think the problem is that eshell-send-input is resetting the
input target location, so that if the asynchronous process is not done
by the time the next RET is received, the input processor thinks
that the input is meant for the process; which, when smart display is
enabled, will be the text of the last command line! That is a bug in
itself.
In holding down RET while an asynchronous process is running,
there will be a point in between termination of the process, and the
running of eshell-post-command-hook, which would cause
eshell-send-input to call eshell-copy-old-input, and then
process that text as a command to be run after the process. Perhaps
there should be a way of killing pending input between the death of the
process, and the post-command-hook.
Perhaps toggled by a command, that makes each output block a smart display block.
The reason for the failure of the last disk command, or the text of the last Lisp error.
A special associate array, which can take references of the form ‘$=[REGEXP]’. It indexes into the directory ring.
info alias that can take argumentsSo that the user can enter ‘info chmod’, for example.
eshell-browseIt would treat the Eshell buffer as an outline. Collapsing the outline hides all of the output text. Collapsing again would show only the first command run in each directory
This would be expanded by eshell-expand-file-name (see above).
If it’s a Lisp function, input redirection implies xargs (in a
way…). If input redirection is added, also update the
file-name-quote-list, and the delimiter list.
With the handling of word specified by an
eshell-special-alist.
eshell-eval-using-options, allow a :complete tagIt would be used to provide completion rules for that command. Then the macro will automagically define the completion function.
eshell-command-on-region, apply redirections to the resultSo that ‘+ > 'blah’ would cause the result of the + (using
input from the current region) to be inserting into the symbol
blah.
If an external command is being invoked, the input is sent as standard input, as if a ‘cat <region> |’ had been invoked.
If a Lisp command, or an alias, is invoked, then if the line has no
newline characters, it is divided by whitespace and passed as arguments
to the Lisp function. Otherwise, it is divided at the newline
characters. Thus, invoking + on a series of numbers will add
them; min would display the smallest figure, etc.
eshell-script-mode as a minor modeIt would provide syntax, abbrev, highlighting and indenting support like
emacs-lisp-mode and shell-mode.
This means ‘!n’, ‘!#’, ‘!:%’, and ‘!:1-’ as separate from ‘!:1*’.
historyfc in LispThis would allow for an “output translators”, that take a function to modify output with, and a target. Devise a syntax that works well with pipes, and can accommodate multiple functions (i.e., ‘>'(upcase regexp-quote)’ or ‘>'upcase’).
This would be optional, rather than always using the Eshell buffer. This would allow it to be run from the command line (perhaps).
help commandIt would call subcommands with --help, or -h or /?, as appropriate.
stty in Lisprc’s matching operator, e.g., ‘~ (list) regexp’bg and fg as editors of eshell-process-listUsing bg on a process that is already in the background does
nothing. Specifying redirection targets replaces (or adds) to the list
current being used.
jobs print only the processes for the current shellThe syntax table for parsing these should be customizable, such that the user could change it to use rc syntax: ‘>[2=1]’.
Return them as a list, so that ‘$_[*]’ is all the arguments of the last command.
Make it possible for the user to send char-by-char to the underlying process. Ultimately, I should be able to move away from using term.el altogether, since everything but the ANSI code handling is already part of Eshell. Then, things would work correctly on MS-Windows as well (which doesn’t have /bin/sh, although term.el tries to use it).
That is, make (su, bash, telnet,
rlogin, rsh, etc.) be part of
eshell-visual-commands. The only exception is if the shell is
being used to invoke a single command. Then, the behavior should be
based on what that command is.
openThis would search for some way to open its argument (similar to opening a file in the Windows Explorer).
read to be the same as open, only read-onlytail command which uses view-fileIt would move point to the end of the buffer, and then turns on
auto-revert mode in that buffer at frequent intervals—and a
head alias which assumes an upper limit of
eshell-maximum-line-length characters per line.
dgrep load dired, mark everything, then invoke dired-do-searchThis would run Emacs with the appropriate arguments to invoke Eshell only. That way, it could be listed as a login shell.
PS2 string for multi-line input promptsTERMCAP usageeshell-send-input
So that it automatically expands and corrects pathnames. Or make pathname completion for Pcomplete auto-expand ‘/u/i/stdTAB’ to ‘/usr/include/stdTAB’.
pushd stack to disk along with last-dir-ringeshell/cat which would allow it to sort and uniqwc in LispAdd support for counting sentences, paragraphs, pages, etc.
sort and uniq in Lisptouch in Lispcomm in Lispepatch command in LispThis would call ediff-patch-file, or ediff-patch-buffer,
depending on its argument.
xargs based on command rewritingThat is, ‘find X | xargs Y’ would be indicated using ‘Y
${find X}’. Maybe eshell-do-pipelines could be changed to
perform this on-thy-fly rewriting.
less that brings up a view-mode bufferSuch that the user can press SPC and DEL, and then q to return to Eshell. It would be equivalent to: ‘X > #<buffer Y>; view-buffer #<buffer Y>’.
eshell-mode as much a full citizen as shell-modeEverywhere in Emacs where shell-mode is specially noticed, add
eshell-mode there.
cp targeteshell-commandIf the first thing that I do after entering Emacs is to run
eshell-command and invoke ls, and then use M-x
eshell, it doesn’t display anything.
Since it keeps the cursor up where the command was invoked.
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The purpose of this License is to make a manual, textbook, or other functional and useful document free in the sense of freedom: to assure everyone the effective freedom to copy and redistribute it, with or without modifying it, either commercially or noncommercially. Secondarily, this License preserves for the author and publisher a way to get credit for their work, while not being considered responsible for modifications made by others.
This License is a kind of “copyleft”, which means that derivative works of the document must themselves be free in the same sense. It complements the GNU General Public License, which is a copyleft license designed for free software.
We have designed this License in order to use it for manuals for free software, because free software needs free documentation: a free program should come with manuals providing the same freedoms that the software does. But this License is not limited to software manuals; it can be used for any textual work, regardless of subject matter or whether it is published as a printed book. We recommend this License principally for works whose purpose is instruction or reference.
This License applies to any manual or other work, in any medium, that contains a notice placed by the copyright holder saying it can be distributed under the terms of this License. Such a notice grants a world-wide, royalty-free license, unlimited in duration, to use that work under the conditions stated herein. The “Document”, below, refers to any such manual or work. Any member of the public is a licensee, and is addressed as “you”. You accept the license if you copy, modify or distribute the work in a way requiring permission under copyright law.
A “Modified Version” of the Document means any work containing the Document or a portion of it, either copied verbatim, or with modifications and/or translated into another language.
A “Secondary Section” is a named appendix or a front-matter section of the Document that deals exclusively with the relationship of the publishers or authors of the Document to the Document’s overall subject (or to related matters) and contains nothing that could fall directly within that overall subject. (Thus, if the Document is in part a textbook of mathematics, a Secondary Section may not explain any mathematics.) The relationship could be a matter of historical connection with the subject or with related matters, or of legal, commercial, philosophical, ethical or political position regarding them.
The “Invariant Sections” are certain Secondary Sections whose titles are designated, as being those of Invariant Sections, in the notice that says that the Document is released under this License. If a section does not fit the above definition of Secondary then it is not allowed to be designated as Invariant. The Document may contain zero Invariant Sections. If the Document does not identify any Invariant Sections then there are none.
The “Cover Texts” are certain short passages of text that are listed, as Front-Cover Texts or Back-Cover Texts, in the notice that says that the Document is released under this License. A Front-Cover Text may be at most 5 words, and a Back-Cover Text may be at most 25 words.
A “Transparent” copy of the Document means a machine-readable copy, represented in a format whose specification is available to the general public, that is suitable for revising the document straightforwardly with generic text editors or (for images composed of pixels) generic paint programs or (for drawings) some widely available drawing editor, and that is suitable for input to text formatters or for automatic translation to a variety of formats suitable for input to text formatters. A copy made in an otherwise Transparent file format whose markup, or absence of markup, has been arranged to thwart or discourage subsequent modification by readers is not Transparent. An image format is not Transparent if used for any substantial amount of text. A copy that is not “Transparent” is called “Opaque”.
Examples of suitable formats for Transparent copies include plain ASCII without markup, Texinfo input format, LaTeX input format, SGML or XML using a publicly available DTD, and standard-conforming simple HTML, PostScript or PDF designed for human modification. Examples of transparent image formats include PNG, XCF and JPG. Opaque formats include proprietary formats that can be read and edited only by proprietary word processors, SGML or XML for which the DTD and/or processing tools are not generally available, and the machine-generated HTML, PostScript or PDF produced by some word processors for output purposes only.
The “Title Page” means, for a printed book, the title page itself, plus such following pages as are needed to hold, legibly, the material this License requires to appear in the title page. For works in formats which do not have any title page as such, “Title Page” means the text near the most prominent appearance of the work’s title, preceding the beginning of the body of the text.
The “publisher” means any person or entity that distributes copies of the Document to the public.
A section “Entitled XYZ” means a named subunit of the Document whose title either is precisely XYZ or contains XYZ in parentheses following text that translates XYZ in another language. (Here XYZ stands for a specific section name mentioned below, such as “Acknowledgements”, “Dedications”, “Endorsements”, or “History”.) To “Preserve the Title” of such a section when you modify the Document means that it remains a section “Entitled XYZ” according to this definition.
The Document may include Warranty Disclaimers next to the notice which states that this License applies to the Document. These Warranty Disclaimers are considered to be included by reference in this License, but only as regards disclaiming warranties: any other implication that these Warranty Disclaimers may have is void and has no effect on the meaning of this License.
You may copy and distribute the Document in any medium, either commercially or noncommercially, provided that this License, the copyright notices, and the license notice saying this License applies to the Document are reproduced in all copies, and that you add no other conditions whatsoever to those of this License. You may not use technical measures to obstruct or control the reading or further copying of the copies you make or distribute. However, you may accept compensation in exchange for copies. If you distribute a large enough number of copies you must also follow the conditions in section 3.
You may also lend copies, under the same conditions stated above, and you may publicly display copies.
If you publish printed copies (or copies in media that commonly have printed covers) of the Document, numbering more than 100, and the Document’s license notice requires Cover Texts, you must enclose the copies in covers that carry, clearly and legibly, all these Cover Texts: Front-Cover Texts on the front cover, and Back-Cover Texts on the back cover. Both covers must also clearly and legibly identify you as the publisher of these copies. The front cover must present the full title with all words of the title equally prominent and visible. You may add other material on the covers in addition. Copying with changes limited to the covers, as long as they preserve the title of the Document and satisfy these conditions, can be treated as verbatim copying in other respects.
If the required texts for either cover are too voluminous to fit legibly, you should put the first ones listed (as many as fit reasonably) on the actual cover, and continue the rest onto adjacent pages.
If you publish or distribute Opaque copies of the Document numbering more than 100, you must either include a machine-readable Transparent copy along with each Opaque copy, or state in or with each Opaque copy a computer-network location from which the general network-using public has access to download using public-standard network protocols a complete Transparent copy of the Document, free of added material. If you use the latter option, you must take reasonably prudent steps, when you begin distribution of Opaque copies in quantity, to ensure that this Transparent copy will remain thus accessible at the stated location until at least one year after the last time you distribute an Opaque copy (directly or through your agents or retailers) of that edition to the public.
It is requested, but not required, that you contact the authors of the Document well before redistributing any large number of copies, to give them a chance to provide you with an updated version of the Document.
You may copy and distribute a Modified Version of the Document under the conditions of sections 2 and 3 above, provided that you release the Modified Version under precisely this License, with the Modified Version filling the role of the Document, thus licensing distribution and modification of the Modified Version to whoever possesses a copy of it. In addition, you must do these things in the Modified Version:
If the Modified Version includes new front-matter sections or appendices that qualify as Secondary Sections and contain no material copied from the Document, you may at your option designate some or all of these sections as invariant. To do this, add their titles to the list of Invariant Sections in the Modified Version’s license notice. These titles must be distinct from any other section titles.
You may add a section Entitled “Endorsements”, provided it contains nothing but endorsements of your Modified Version by various parties—for example, statements of peer review or that the text has been approved by an organization as the authoritative definition of a standard.
You may add a passage of up to five words as a Front-Cover Text, and a passage of up to 25 words as a Back-Cover Text, to the end of the list of Cover Texts in the Modified Version. Only one passage of Front-Cover Text and one of Back-Cover Text may be added by (or through arrangements made by) any one entity. If the Document already includes a cover text for the same cover, previously added by you or by arrangement made by the same entity you are acting on behalf of, you may not add another; but you may replace the old one, on explicit permission from the previous publisher that added the old one.
The author(s) and publisher(s) of the Document do not by this License give permission to use their names for publicity for or to assert or imply endorsement of any Modified Version.
You may combine the Document with other documents released under this License, under the terms defined in section 4 above for modified versions, provided that you include in the combination all of the Invariant Sections of all of the original documents, unmodified, and list them all as Invariant Sections of your combined work in its license notice, and that you preserve all their Warranty Disclaimers.
The combined work need only contain one copy of this License, and multiple identical Invariant Sections may be replaced with a single copy. If there are multiple Invariant Sections with the same name but different contents, make the title of each such section unique by adding at the end of it, in parentheses, the name of the original author or publisher of that section if known, or else a unique number. Make the same adjustment to the section titles in the list of Invariant Sections in the license notice of the combined work.
In the combination, you must combine any sections Entitled “History” in the various original documents, forming one section Entitled “History”; likewise combine any sections Entitled “Acknowledgements”, and any sections Entitled “Dedications”. You must delete all sections Entitled “Endorsements.”
You may make a collection consisting of the Document and other documents released under this License, and replace the individual copies of this License in the various documents with a single copy that is included in the collection, provided that you follow the rules of this License for verbatim copying of each of the documents in all other respects.
You may extract a single document from such a collection, and distribute it individually under this License, provided you insert a copy of this License into the extracted document, and follow this License in all other respects regarding verbatim copying of that document.
A compilation of the Document or its derivatives with other separate and independent documents or works, in or on a volume of a storage or distribution medium, is called an “aggregate” if the copyright resulting from the compilation is not used to limit the legal rights of the compilation’s users beyond what the individual works permit. When the Document is included in an aggregate, this License does not apply to the other works in the aggregate which are not themselves derivative works of the Document.
If the Cover Text requirement of section 3 is applicable to these copies of the Document, then if the Document is less than one half of the entire aggregate, the Document’s Cover Texts may be placed on covers that bracket the Document within the aggregate, or the electronic equivalent of covers if the Document is in electronic form. Otherwise they must appear on printed covers that bracket the whole aggregate.
Translation is considered a kind of modification, so you may distribute translations of the Document under the terms of section 4. Replacing Invariant Sections with translations requires special permission from their copyright holders, but you may include translations of some or all Invariant Sections in addition to the original versions of these Invariant Sections. You may include a translation of this License, and all the license notices in the Document, and any Warranty Disclaimers, provided that you also include the original English version of this License and the original versions of those notices and disclaimers. In case of a disagreement between the translation and the original version of this License or a notice or disclaimer, the original version will prevail.
If a section in the Document is Entitled “Acknowledgements”, “Dedications”, or “History”, the requirement (section 4) to Preserve its Title (section 1) will typically require changing the actual title.
You may not copy, modify, sublicense, or distribute the Document except as expressly provided under this License. Any attempt otherwise to copy, modify, sublicense, or distribute it is void, and will automatically terminate your rights under this License.
However, if you cease all violation of this License, then your license from a particular copyright holder is reinstated (a) provisionally, unless and until the copyright holder explicitly and finally terminates your license, and (b) permanently, if the copyright holder fails to notify you of the violation by some reasonable means prior to 60 days after the cessation.
Moreover, your license from a particular copyright holder is reinstated permanently if the copyright holder notifies you of the violation by some reasonable means, this is the first time you have received notice of violation of this License (for any work) from that copyright holder, and you cure the violation prior to 30 days after your receipt of the notice.
Termination of your rights under this section does not terminate the licenses of parties who have received copies or rights from you under this License. If your rights have been terminated and not permanently reinstated, receipt of a copy of some or all of the same material does not give you any rights to use it.
The Free Software Foundation may publish new, revised versions of the GNU Free Documentation License from time to time. Such new versions will be similar in spirit to the present version, but may differ in detail to address new problems or concerns. See https://www.gnu.org/licenses/.
Each version of the License is given a distinguishing version number. If the Document specifies that a particular numbered version of this License “or any later version” applies to it, you have the option of following the terms and conditions either of that specified version or of any later version that has been published (not as a draft) by the Free Software Foundation. If the Document does not specify a version number of this License, you may choose any version ever published (not as a draft) by the Free Software Foundation. If the Document specifies that a proxy can decide which future versions of this License can be used, that proxy’s public statement of acceptance of a version permanently authorizes you to choose that version for the Document.
“Massive Multiauthor Collaboration Site” (or “MMC Site”) means any World Wide Web server that publishes copyrightable works and also provides prominent facilities for anybody to edit those works. A public wiki that anybody can edit is an example of such a server. A “Massive Multiauthor Collaboration” (or “MMC”) contained in the site means any set of copyrightable works thus published on the MMC site.
“CC-BY-SA” means the Creative Commons Attribution-Share Alike 3.0 license published by Creative Commons Corporation, a not-for-profit corporation with a principal place of business in San Francisco, California, as well as future copyleft versions of that license published by that same organization.
“Incorporate” means to publish or republish a Document, in whole or in part, as part of another Document.
An MMC is “eligible for relicensing” if it is licensed under this License, and if all works that were first published under this License somewhere other than this MMC, and subsequently incorporated in whole or in part into the MMC, (1) had no cover texts or invariant sections, and (2) were thus incorporated prior to November 1, 2008.
The operator of an MMC Site may republish an MMC contained in the site under CC-BY-SA on the same site at any time before August 1, 2009, provided the MMC is eligible for relicensing.
To use this License in a document you have written, include a copy of the License in the document and put the following copyright and license notices just after the title page:
Copyright (C) year your name. Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, no Front-Cover Texts, and no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''.
If you have Invariant Sections, Front-Cover Texts and Back-Cover Texts, replace the “with…Texts.” line with this:
with the Invariant Sections being list their titles, with
the Front-Cover Texts being list, and with the Back-Cover Texts
being list.
If you have Invariant Sections without Cover Texts, or some other combination of the three, merge those two alternatives to suit the situation.
If your document contains nontrivial examples of program code, we recommend releasing these examples in parallel under your choice of free software license, such as the GNU General Public License, to permit their use in free software.
| Index Entry | Section | ||
|---|---|---|---|
| | |||
| . | |||
| .: | Scripts | ||
| | |||
| A | |||
| addpath: | Built-ins | ||
| agrep: | Built-ins | ||
| alias: | Built-ins | ||
| | |||
| C | |||
| cd: | Built-ins | ||
| clear: | Built-ins | ||
| | |||
| D | |||
| date: | Built-ins | ||
| define: | Built-ins | ||
| diff: | Built-ins | ||
| | |||
| E | |||
| egrep: | Built-ins | ||
| | |||
| F | |||
| fgrep: | Built-ins | ||
| | |||
| G | |||
| glimpse: | Built-ins | ||
| grep: | Built-ins | ||
| | |||
| H | |||
| history: | History | ||
| | |||
| I | |||
| info: | Built-ins | ||
| | |||
| J | |||
| jobs: | Built-ins | ||
| | |||
| K | |||
| kill: | Built-ins | ||
| | |||
| L | |||
| listify: | Built-ins | ||
| locate: | Built-ins | ||
| | |||
| M | |||
| make: | Built-ins | ||
| | |||
| O | |||
| occur: | Built-ins | ||
| | |||
| P | |||
| printnl: | Built-ins | ||
| | |||
| S | |||
| source: | Scripts | ||
| su: | Built-ins | ||
| sudo: | Built-ins | ||
| | |||
This is comparable to viewing the contents of a folder using a graphical display.
For the understandably curious, here is what that command
looks like: But don’t let it fool you; once you know what’s going on,
it’s easier than it looks: ls -lt **/*.doc(Lk+50aM+5).
To see the Lisp form that will be invoked, type: ‘eshell-parse-command "echo hello"’
Read-Eval-Print Loop
Command completion, as opposed to code completion, which is beyond the scope of pcomplete.
Eshell has no string-manipulation expansions because the Elisp library already provides many functions for this.
E.g., entering just ‘$var’ at the prompt
is equivalent to entering the value of var at the prompt.
See Easy Customization in The GNU Emacs Manual.
ERC provides a similar module facility.
See Customization in The Emacs Lisp Reference Manual.
If the module has no user-customizable options, then there is no need to define it as an Eshell module.