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 (@pxref{Lisp
-Interaction, Emacs Lisp Interaction, , emacs, The Emacs Editor})
-REPL@footnote{Short for ``Read-Eval-Print Loop''.} for Emacs
-@emph{and} with an interface similar to command shells such as
-@command{bash}, @command{zsh}, @command{rc}, or @command{4dos}.
+Interaction, , , emacs, The Emacs Editor}) REPL@footnote{Short for
+``Read-Eval-Print Loop''.} for Emacs @emph{and} with an interface
+similar to command shells such as @command{bash}, @command{zsh},
+@command{rc}, or @command{4dos}.
@c This manual is updated to release 2.4 of Eshell.
@insertcopying
@section Invocation
Eshell is both a command shell and an Emacs Lisp @acronym{REPL}. As a
result, you can invoke commands in two different ways: in @dfn{command
-form} or in @dfn{lisp form}.
+form} or in @dfn{Lisp form}.
You can use the semicolon (@code{;}) to separate multiple command
invocations on a single line, executing each in turn. You can also
(1 2 3)
@end example
-Additionally, many built-in Eshell commands (@pxref{Built-ins, Eshell
-commands}) will flatten the arguments they receive, so passing a list
-as an argument will ``spread'' the elements into multiple arguments:
+Additionally, many built-in Eshell commands (@pxref{Built-ins}) will
+flatten the arguments they receive, so passing a list as an argument
+will ``spread'' the elements into multiple arguments:
@example
~ $ printnl (list 1 2) 3
@item #<process @var{name}>
Return the process named @var{name}. This is equivalent to
-@samp{$(get-process "@var{name}")} (@pxref{Process Information, , ,
+@samp{$(get-process "@var{name}")} (@pxref{Process Information, , ,
elisp, The Emacs Lisp Reference Manual}).
@end table
@node Built-ins
@section Built-in commands
-Several commands are built-in in Eshell. In order to call the
-external variant of a built-in command @code{foo}, you could call
-@code{*foo}. Usually, this should not be necessary. You can check
-what will be applied by the @code{which} command:
+Eshell provides a number of built-in commands, many of them
+implementing common command-line utilities, but enhanced for Eshell.
+(These built-in commands are just ordinary Lisp functions whose names
+begin with @code{eshell/}.) In order to call the external variant of
+a built-in command @code{foo}, you could call @code{*foo}. Usually,
+this should not be necessary. You can check what will be applied by
+the @code{which} command:
@example
~ $ which ls
@item $INSIDE_EMACS
This variable indicates to external commands that they are being
invoked from within Emacs so they can adjust their behavior if
-necessary. Its value is @code{@var{emacs-version},eshell}.
+necessary. By default, its value is
+@code{@var{emacs-version},eshell}. Other parts of Emacs, such as
+Tramp, may add extra information to this value.
@end table
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 @key{TAB} will behave similarly to completion in
-@code{elisp-mode} and @code{lisp-interaction-mode}. For glob patterns, the
-pattern will be removed from the input line, and replaced by the
-completion.
+Eshell completion also works for Lisp forms and glob patterns. If the
+point is on a Lisp form, then @key{TAB} will behave similarly to
+completion in @code{elisp-mode} and @code{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 @code{completion-cycle-threshold}), press @kbd{M-?}.
@node Control Flow
@section Control Flow
-Because Eshell commands can not (easily) be combined with lisp forms,
+Because Eshell commands can not (easily) be combined with Lisp forms,
Eshell provides command-oriented control flow statements for
convenience.
@item a sequence
Expands to the element at the (zero-based) index @var{i} of the
-sequence (@pxref{Sequences Arrays Vectors, Sequences, , elisp, The
-Emacs Lisp Reference Manual}).
+sequence (@pxref{Sequences Arrays Vectors, , , elisp, The Emacs Lisp
+Reference Manual}).
@item a string
Split the string at whitespace, and then expand to the @var{i}th
systems. You can control this behavior via the
@code{eshell-glob-case-insensitive} option. You can further customize
the syntax and behavior of globbing in Eshell via the Customize group
-``eshell-glob'' (@pxref{Easy Customization, , , emacs, The GNU Emacs
-Manual}).
+@code{eshell-glob} (@pxref{Easy Customization, , , emacs, The GNU
+Emacs Manual}).
@table @samp
@code{[@dots{}]}, @code{<@dots{}>}, or @code{@{@dots{}@}}.
You can customize the syntax and behavior of predicates and modifiers
-in Eshell via the Customize group ``eshell-pred'' (@pxref{Easy
+in Eshell via the Customize group @code{eshell-pred} (@pxref{Easy
Customization, , , emacs, The GNU Emacs Manual}).
@menu
Redirect output to @var{dest}, appending it to the existing contents
of @var{dest}.
-@item >>> @var{buffer}
-@itemx @var{fd}>>> @var{buffer}
+@item >>> @var{dest}
+@itemx @var{fd}>>> @var{dest}
Redirect output to @var{dest}, inserting it at the current mark if
@var{dest} is a buffer, at the beginning of the file if @var{dest} is
a file, or otherwise behaving the same as @code{>>}.
-@item &> @var{file}
-@itemx >& @var{file}
+@item &> @var{dest}
+@itemx >& @var{dest}
Redirect both standard output and standard error to @var{dest},
overwriting its contents with the new output.
-@item &>> @var{file}
-@itemx >>& @var{file}
+@item &>> @var{dest}
+@itemx >>& @var{dest}
Redirect both standard output and standard error to @var{dest},
appending it to the existing contents of @var{dest}.
-@item &>>> @var{file}
-@itemx >>>& @var{file}
+@item &>>> @var{dest}
+@itemx >>>& @var{dest}
Redirect both standard output and standard error to @var{dest},
-inserting it like with @code{>>> @var{file}}.
+inserting it like with @code{>>> @var{dest}}.
@item >&@var{other-fd}
@itemx @var{fd}>&@var{other-fd}
@item Support zsh's ``Parameter Expansion'' syntax, i.e., @samp{$@{@var{name}:-@var{val}@}}
-@item Write an @command{info} alias that can take arguments
-
-So that the user can enter @samp{info chmod}, for example.
-
@item Create a mode @code{eshell-browse}
It would treat the Eshell buffer as an outline. Collapsing the outline
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