@menu
* Minor Modes:: Each minor mode is one feature you can turn on
independently of any others.
+* Easy Customization::
+ Convenient way to browse and change user options.
* Variables:: Many Emacs commands examine Emacs variables
to decide what to do; by setting variables,
you can control their functioning.
The advantage of Transient Mark mode is that Emacs can display the
region highlighted (currently only when using X). @xref{Mark}.
-@node Variables
-@section Variables
-@cindex variable
-@cindex option, user
-@cindex user option
-
- A @dfn{variable} is a Lisp symbol which has a value. The symbol's
-name is also called the name of the variable. A variable name can
-contain any characters that can appear in a file, but conventionally
-variable names consist of words separated by hyphens. A variable can
-have a documentation string which describes what kind of value it should
-have and how the value will be used.
-
- Lisp allows any variable to have any kind of value, but most variables
-that Emacs uses require a value of a certain type. Often the value should
-always be a string, or should always be a number. Sometimes we say that a
-certain feature is turned on if a variable is ``non-@code{nil},'' meaning
-that if the variable's value is @code{nil}, the feature is off, but the
-feature is on for @emph{any} other value. The conventional value to use to
-turn on the feature---since you have to pick one particular value when you
-set the variable---is @code{t}.
-
- Emacs uses many Lisp variables for internal record keeping, as any
-Lisp program must, but the most interesting variables for you are the
-ones that exist for the sake of customization. Emacs does not (usually)
-change the values of these variables; instead, you set the values, and
-thereby alter and control the behavior of certain Emacs commands. These
-variables are called @dfn{user options}. Most user options are
-documented in this manual, and appear in the Variable Index
-(@pxref{Variable Index}).
-
- One example of a variable which is a user option is @code{fill-column}, which
-specifies the position of the right margin (as a number of characters from
-the left margin) to be used by the fill commands (@pxref{Filling}).
-
-@menu
-* Examining:: Examining or setting one variable's value.
-* Easy Customization::
- Convenient and easy customization of variables.
-* Hooks:: Hook variables let you specify programs for parts
- of Emacs to run on particular occasions.
-* Locals:: Per-buffer values of variables.
-* File Variables:: How files can specify variable values.
-@end menu
-
-@node Examining
-@subsection Examining and Setting Variables
-@cindex setting variables
-
-@table @kbd
-@item C-h v @var{var} @key{RET}
-Display the value and documentation of variable @var{var}
-(@code{describe-variable}).
-@item M-x set-variable @key{RET} @var{var} @key{RET} @var{value} @key{RET}
-Change the value of variable @var{var} to @var{value}.
-@end table
-
- To examine the value of a single variable, use @kbd{C-h v}
-(@code{describe-variable}), which reads a variable name using the
-minibuffer, with completion. It displays both the value and the
-documentation of the variable. For example,
-
-@example
-C-h v fill-column @key{RET}
-@end example
-
-@noindent
-displays something like this:
-
-@smallexample
-fill-column's value is 70
-
-Documentation:
-*Column beyond which automatic line-wrapping should happen.
-Automatically becomes buffer-local when set in any fashion.
-@end smallexample
-
-@noindent
-The star at the beginning of the documentation indicates that this
-variable is a user option. @kbd{C-h v} is not restricted to user
-options; it allows any variable name.
-
-@findex set-variable
- The most convenient way to set a specific user option is with @kbd{M-x
-set-variable}. This reads the variable name with the minibuffer (with
-completion), and then reads a Lisp expression for the new value using
-the minibuffer a second time. For example,
-
-@example
-M-x set-variable @key{RET} fill-column @key{RET} 75 @key{RET}
-@end example
-
-@noindent
-sets @code{fill-column} to 75.
-
- @kbd{M-x set-variable} is limited to user option variables, but you can
-set any variable with a Lisp expression, using the function @code{setq}.
-Here is a @code{setq} expression to set @code{fill-column}:
-
-@example
-(setq fill-column 75)
-@end example
-
- To execute an expression like this one, go to the @samp{*scratch*}
-buffer, type in the expression, and then type @kbd{C-j}. @xref{Lisp
-Interaction}.
-
- Setting variables, like all means of customizing Emacs except where
-otherwise stated, affects only the current Emacs session.
-
@node Easy Customization
-@subsection Easy Customization Interface
+@section Easy Customization Interface
+
+@cindex user option
+ Emacs has many @dfn{user options} which have values that you can set
+in order to customize various commands. Most user options are
+documented in this manual. Each user option is actually a Lisp
+variable (@pxref{Variables}), so their names appear in the Variable
+Index (@pxref{Variable Index}).
@findex customize
@cindex customization buffer
- A convenient way to find the user option variables that you want to
-change, and then change them, is with @kbd{M-x customize}. This
-command creates a @dfn{customization buffer} with which you can browse
-through the Emacs user options in a logically organized structure,
-then edit and set their values. You can also use the customization
-buffer to save settings permanently in your @file{~/.emacs} file
-(@pxref{Init File}).
-
-The appearance of the example buffers in the following is typically
-different under a window system where faces can be used to indicate the
-active fields and other features.
+ You can browse interactively through the the user options and change
+some of them using @kbd{M-x customize}. This command creates a
+@dfn{customization buffer}, which offers commands to navigate through
+a logically organized structure of the Emacs user options; you can
+also use it to edit and set their values, and to save settings
+permanently in your @file{~/.emacs} file (@pxref{Init File}).
+
+ The appearance of the example buffers in this section is typically
+different under a window system, since faces are then used to indicate
+the active fields and other features.
@menu
* Groups: Customization Groups.
@end menu
@node Customization Groups
-@subsubsection Customization Groups
+@subsection Customization Groups
@cindex customization groups
For customization purposes, user options are organized into
This is the way to set values in it.
@node Changing an Option
-@subsubsection Changing an Option
+@subsection Changing an Option
Here is an example of what a user option looks like in the
customization buffer:
option yet. The word @samp{[State]} at the beginning of this line is
active; you can get a menu of various operations by invoking it with
@kbd{Mouse-1} or @key{RET}. These operations are essential for
-customizing the variable.
+customizing the user option.
The line after the @samp{[State]} line displays the beginning of the
option's documentation string. If there are more lines of
@end smallexample
@cindex setting option value
- Editing the value does not actually set the option variable. To do
+ Editing the value does not actually set the option. To do
that, you must @dfn{set} the option. To do this, invoke the word
@samp{[State]} and choose @samp{Set for Current Session}.
@dfn{saving} the value changes it for future sessions as well. To
save the option, invoke @samp{[State]} and select the @samp{Save for
Future Sessions} operation. This works by writing code so as to set
-the option variable again each time you start Emacs (@pxref{Saving
+the option again, each time you start Emacs (@pxref{Saving
Customizations}).
You can also restore the option to its standard value by invoking
@item Use Backup Value
This sets the option to a previous value that was set in the
-customization buffer in this session. If you customize a variable
-and then reset the variable, which discards the customized value,
+customization buffer in this session. If you customize an option
+and then reset it, which discards the customized value,
you can get the customized value back again with this operation.
@end table
set, saved or reset.
@node Saving Customizations
-@subsubsection Saving Customizations
+@subsection Saving Customizations
@vindex custom-file
The customization buffer normally saves customizations in
customizations you might have on your init file.
@node Face Customization
-@subsubsection Customizing Faces
+@subsection Customizing Faces
@cindex customizing faces
@cindex bold font
@cindex italic font
to clear out the attribute.
@node Specific Customization
-@subsubsection Customizing Specific Items
+@subsection Customizing Specific Items
Instead of finding the options you want to change by moving down
through the structure of groups, you can specify the particular option,
@end table
@findex customize-option
- If you want to alter a particular user option variable with the
+ If you want to alter a particular user option with the
customization buffer, and you know its name, you can use the command
@kbd{M-x customize-option} and specify the option name. This sets up
the customization buffer with just one option---the one that you asked
@findex customize-group
You can also set up the customization buffer with a specific group,
using @kbd{M-x customize-group}. The immediate contents of the chosen
-group, including option variables, faces, and other groups, all appear
+group, including user options, faces, and other groups, all appear
as well. However, these subgroups' own contents start out hidden. You
can show their contents in the usual way, by invoking @samp{[Show]}.
saved. Use @kbd{M-x customize-customized} to look at the options and
faces that you have set but not saved.
+@node Variables
+@section Variables
+@cindex variable
+@cindex option, user
+@cindex user option
+
+ A @dfn{variable} is a Lisp symbol which has a value. The symbol's
+name is also called the name of the variable. A variable name can
+contain any characters that can appear in a file, but conventionally
+variable names consist of words separated by hyphens. A variable can
+have a documentation string which describes what kind of value it should
+have and how the value will be used.
+
+ Lisp allows any variable to have any kind of value, but most variables
+that Emacs uses need a value of a certain type. Often the value should
+always be a string, or should always be a number. Sometimes we say that a
+certain feature is turned on if a variable is ``non-@code{nil},'' meaning
+that if the variable's value is @code{nil}, the feature is off, but the
+feature is on for @emph{any} other value. The conventional value to use to
+turn on the feature---since you have to pick one particular value when you
+set the variable---is @code{t}.
+
+ Emacs uses many Lisp variables for internal record keeping, but the
+most interesting variables for a non-programmer user are the @dfn{user
+options}, the variables that are meant for users to change. Each user
+option that you can set with the customization buffera is, in fact, a
+Lisp variable. Emacs does not (usually) change the values of these
+variables; instead, you set the values, and thereby alter and control
+the behavior of certain Emacs commands. Use of the customization
+buffer is explained above; here we describe other aspects of Emacs
+variables.
+
+@menu
+* Examining:: Examining or setting one variable's value.
+* Hooks:: Hook variables let you specify programs for parts
+ of Emacs to run on particular occasions.
+* Locals:: Per-buffer values of variables.
+* File Variables:: How files can specify variable values.
+@end menu
+
+@node Examining
+@subsection Examining and Setting Variables
+@cindex setting variables
+
+@table @kbd
+@item C-h v @var{var} @key{RET}
+Display the value and documentation of variable @var{var}
+(@code{describe-variable}).
+@item M-x set-variable @key{RET} @var{var} @key{RET} @var{value} @key{RET}
+Change the value of variable @var{var} to @var{value}.
+@end table
+
+ To examine the value of a single variable, use @kbd{C-h v}
+(@code{describe-variable}), which reads a variable name using the
+minibuffer, with completion. It displays both the value and the
+documentation of the variable. For example,
+
+@example
+C-h v fill-column @key{RET}
+@end example
+
+@noindent
+displays something like this:
+
+@smallexample
+fill-column's value is 70
+
+Documentation:
+*Column beyond which automatic line-wrapping should happen.
+Automatically becomes buffer-local when set in any fashion.
+@end smallexample
+
+@noindent
+The star at the beginning of the documentation indicates that this
+variable is a user option. @kbd{C-h v} is not restricted to user
+options; it allows any variable name.
+
+@findex set-variable
+ The most convenient way to set a specific user option is with @kbd{M-x
+set-variable}. This reads the variable name with the minibuffer (with
+completion), and then reads a Lisp expression for the new value using
+the minibuffer a second time. For example,
+
+@example
+M-x set-variable @key{RET} fill-column @key{RET} 75 @key{RET}
+@end example
+
+@noindent
+sets @code{fill-column} to 75.
+
+ @kbd{M-x set-variable} is limited to user option variables, but you can
+set any variable with a Lisp expression, using the function @code{setq}.
+Here is a @code{setq} expression to set @code{fill-column}:
+
+@example
+(setq fill-column 75)
+@end example
+
+ To execute an expression like this one, go to the @samp{*scratch*}
+buffer, type in the expression, and then type @kbd{C-j}. @xref{Lisp
+Interaction}.
+
+ Setting variables, like all means of customizing Emacs except where
+otherwise stated, affects only the current Emacs session.
+
@node Hooks
@subsection Hooks
@cindex hook
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