C. Command Line Arguments for Emacs Invocation

GNU Emacs supports command line arguments to request various actions when invoking Emacs. These are for compatibility with other editors and for sophisticated activities. We don't recommend using them for ordinary editing.

Arguments starting with `-' are options, and so is `+linenum'. All other arguments specify files to visit. Emacs visits the specified files while it starts up. The last file name on your command line becomes the current buffer; the other files are also visited in other buffers. If there are two files, they are both displayed; otherwise the last file is displayed along with a buffer list that shows what other buffers there are. As with most programs, the special argument `--' says that all subsequent arguments are file names, not options, even if they start with `-'.

Emacs command options can specify many things, such as the size and position of the X window Emacs uses, its colors, and so on. A few options support advanced usage, such as running Lisp functions on files in batch mode. The sections of this chapter describe the available options, arranged according to their purpose.

There are two ways of writing options: the short forms that start with a single `-', and the long forms that start with `--'. For example, `-d' is a short form and `--display' is the corresponding long form.

The long forms with `--' are easier to remember, but longer to type. However, you don't have to spell out the whole option name; any unambiguous abbreviation is enough. When a long option takes an argument, you can use either a space or an equal sign to separate the option name and the argument. Thus, you can write either `--display sugar-bombs:0.0' or `--display=sugar-bombs:0.0'. We recommend an equal sign because it makes the relationship clearer, and the tables below always show an equal sign.

Most options specify how to initialize Emacs, or set parameters for the Emacs session. We call them initial options. A few options specify things to do: for example, load libraries, call functions, or terminate Emacs. These are called action options. These and file names together are called action arguments. Emacs processes all the action arguments in the order they are written. The `.emacs' file can access the values of the action arguments as the elements of a list in the variable command-line-args.

C.1 Action Arguments

Here is a table of the action arguments and options:

` file'

` --file=file'

` --find-file=file'

` --visit=file'

Visit file using find-file. See section Visiting Files. If you visit several files at startup in this way, Emacs also displays a Buffer Menu buffer to show you what files it has visited. You can inhibit that by setting inhibit-startup-buffer-menu to t.

` +linenum file'

Visit file using find-file, then go to line number linenum in it.

` +linenum:columnnum file'

Visit file using find-file, then go to line number linenum and put point at column number columnnum.

` -l file'

` --load=file'

Load a Lisp library named file with the function load. See section Libraries of Lisp Code for Emacs. If file is not an absolute file name, the library can be found either in the current directory, or in the Emacs library search path as specified with EMACSLOADPATH (see section General Variables).

Warning: If previous command-line arguments have visited files, the current directory is the directory of the last file visited.

` -L dir'

` --directory=dir'

Add directory dir to the variable load-path.

` -f function'

` --funcall=function'

Call Lisp function function. If it is an interactive function (a command), it reads the arguments interactively just as if you had called the same function with a key sequence. Otherwise, it calls the function with no arguments.

` --eval=expression'

` --execute=expression'

Evaluate Lisp expression expression.

` --insert=file'

Insert the contents of file into the current buffer. This is like what M-x insert-file does. See section Miscellaneous File Operations.

` --kill'

Exit from Emacs without asking for confirmation.

` --help'

Print a usage message listing all available options, then exit successfully.

` --version'

Print Emacs version, then exit successfully.

C.2 Initial Options

The initial options specify parameters for the Emacs session. This section describes the more general initial options; some other options specifically related to the X Window System appear in the following sections.

Some initial options affect the loading of init files. The normal actions of Emacs are to first load `site-start.el' if it exists, then your own init file `~/.emacs' if it exists, and finally `default.el' if it exists. See section The Init File, `~/.emacs'. Certain options prevent loading of some of these files or substitute other files for them.

` -t device'

` --terminal=device'

Use device as the device for terminal input and output. `--terminal' implies `--no-window-system'.

` -d display'

` --display=display'

Use the X Window System and use the display named display to open the initial Emacs frame. See section Specifying the Display Name, for more details.

` -nw'

` --no-window-system'

Don't communicate directly with the window system, disregarding the DISPLAY environment variable even if it is set. This means that Emacs uses the terminal from which it was launched for all its display and input.

` -batch'

` --batch'

Run Emacs in batch mode. Batch mode is used for running programs written in Emacs Lisp from shell scripts, makefiles, and so on. You should also use the `-l', `-f' or `--eval' option, to invoke a Lisp program to do batch processing.

In batch mode, Emacs does not display the text being edited, and the standard terminal interrupt characters such as C-z and C-c continue to have their normal effect. The functions prin1, princ and print output to stdout instead of the echo area, while message and error messages output to stderr. Functions that would normally read from the minibuffer take their input from stdin instead.

`--batch' implies `-q' (do not load an init file), but `site-start.el' is loaded nonetheless. It also causes Emacs to exit after processing all the command options. In addition, it disables auto-saving except in buffers for which it has been explicitly requested.

` --script file'

Run Emacs in batch mode, like `--batch', and then read and execute the Lisp code in file.

The normal use of this option is in executable script files that run Emacs. They can start with this text on the first line

#!/usr/bin/emacs --script

which will invoke Emacs with `--script' and supply the name of the script file as file. Emacs Lisp then treats `#!' as a comment delimiter.

` -q'

` --no-init-file'

Do not load your Emacs init file `~/.emacs', or `default.el' either. Regardless of this switch, `site-start.el' is still loaded. When invoked like this, Emacs does not allow saving options changed with the M-x customize command and its variants. See section Easy Customization Interface.

` --no-site-file'

Do not load `site-start.el'. The options `-q', `-u' and `--batch' have no effect on the loading of this file--this option and `-Q' are the only options that block it.

` -Q'

` --quick'

Start emacs with minimum customizations. This is like using `-q' and `--no-site-file', but also disables the startup screen.

` --no-splash'

Do not display a splash screen on startup. You can also achieve this effect by setting the variable inhibit-splash-screen to non-nil in you personal init file (but not in `site-start.el'). (This variable was called inhibit-startup-message in previous Emacs versions.)

` --no-desktop'

Do not reload any saved desktop. See section Saving Emacs Sessions.

` -u user'

` --user=user'

Load user's Emacs init file `~user/.emacs' instead of your own(21).

` --debug-init'

Enable the Emacs Lisp debugger for errors in the init file. See (elisp)Error Debugging section `Entering the Debugger on an Error' in The GNU Emacs Lisp Reference Manual.

` --unibyte'

` --no-multibyte'

Do almost everything with single-byte buffers and strings. All buffers and strings are unibyte unless you (or a Lisp program) explicitly ask for a multibyte buffer or string. (Note that Emacs always loads Lisp files in multibyte mode, even if `--unibyte' is specified; see Enabling Multibyte Characters.) Setting the environment variable EMACS_UNIBYTE has the same effect (see section General Variables).

` --multibyte'

` --no-unibyte'

Inhibit the effect of EMACS_UNIBYTE, so that Emacs uses multibyte characters by default, as usual.

C.3 Command Argument Example

Here is an example of using Emacs with arguments and options. It assumes you have a Lisp program file called `hack-c.el' which, when loaded, performs some useful operation on the current buffer, expected to be a C program.

emacs --batch foo.c -l hack-c -f save-buffer >& log

This says to visit `foo.c', load `hack-c.el' (which makes changes in the visited file), save `foo.c' (note that save-buffer is the function that C-x C-s is bound to), and then exit back to the shell (because of `--batch'). `--batch' also guarantees there will be no problem redirecting output to `log', because Emacs will not assume that it has a display terminal to work with.

C.4 Resuming Emacs with Arguments

You can specify action arguments for Emacs when you resume it after a suspension. To prepare for this, put the following code in your `.emacs' file (see section Hooks):

(add-hook 'suspend-hook 'resume-suspend-hook)
(add-hook 'suspend-resume-hook 'resume-process-args)

As further preparation, you must execute the shell script `emacs.csh' (if you use csh as your shell) or `emacs.bash' (if you use bash as your shell). These scripts define an alias named edit, which will resume Emacs giving it new command line arguments such as files to visit. The scripts are found in the `etc' subdirectory of the Emacs distribution.

Only action arguments work properly when you resume Emacs. Initial arguments are not recognized--it's too late to execute them anyway.

Note that resuming Emacs (with or without arguments) must be done from within the shell that is the parent of the Emacs job. This is why edit is an alias rather than a program or a shell script. It is not possible to implement a resumption command that could be run from other subjobs of the shell; there is no way to define a command that could be made the value of EDITOR, for example. Therefore, this feature does not take the place of the Emacs Server feature (see section Using Emacs as a Server).

The aliases use the Emacs Server feature if you appear to have a server Emacs running. However, they cannot determine this with complete accuracy. They may think that a server is still running when in actuality you have killed that Emacs, because the file `/tmp/esrv…' still exists. If this happens, find that file and delete it.

C.5 Environment Variables

The environment is a feature of the operating system; it consists of a collection of variables with names and values. Each variable is called an environment variable; environment variable names are case-sensitive, and it is conventional to use upper case letters only. The values are all text strings.

What makes the environment useful is that subprocesses inherit the environment automatically from their parent process. This means you can set up an environment variable in your login shell, and all the programs you run (including Emacs) will automatically see it. Subprocesses of Emacs (such as shells, compilers, and version-control software) inherit the environment from Emacs, too.

Inside Emacs, the command M-x getenv gets the value of an environment variable. M-x setenv sets a variable in the Emacs environment. (Environment variable substitutions with `$' work in the value just as in file names; see File Names with $.)

The way to set environment variables outside of Emacs depends on the operating system, and especially the shell that you are using. For example, here's how to set the environment variable ORGANIZATION to `not very much' using Bash:

export ORGANIZATION="not very much"

and here's how to do it in csh or tcsh:

setenv ORGANIZATION "not very much"

When Emacs is using the X Window System, various environment variables that control X work for Emacs as well. See the X documentation for more information.

C.5.1 General Variables

Here is an alphabetical list of specific environment variables that have special meanings in Emacs, giving the name of each variable and its meaning. Most of these variables are also used by some other programs. Emacs does not require any of these environment variables to be set, but it uses their values if they are set.

CDPATH

Used by the cd command to search for the directory you specify, when you specify a relative directory name.

EMACS_UNIBYTE

Defining this environment variable with a nonempty value directs Emacs to do almost everything with single-byte buffers and strings. It is equivalent to using the `--unibyte' command-line option on each invocation. See section Initial Options.

EMACSDATA

Directory for the architecture-independent files that come with Emacs. This is used to initialize the Lisp variable data-directory.

EMACSDOC

Directory for the documentation string file, `DOC-emacsversion'. This is used to initialize the Lisp variable doc-directory.

EMACSLOADPATH

A colon-separated list of directories(22) to search for Emacs Lisp files--used to initialize load-path.

EMACSPATH

A colon-separated list of directories to search for executable files--used to initialize exec-path.

EMAIL

Your email address; used to initialize the Lisp variable user-mail-address, which the Emacs mail interface puts into the `From' header of outgoing messages (see section Mail Header Fields).

ESHELL

Used for shell-mode to override the SHELL environment variable.

HISTFILE

The name of the file that shell commands are saved in between logins. This variable defaults to `~/.bash_history' if you use Bash, to `~/.sh_history' if you use ksh, and to `~/.history' otherwise.

HOME

The location of your files in the directory tree; used for expansion of file names starting with a tilde (`~'). On MS-DOS, it defaults to the directory from which Emacs was started, with `/bin' removed from the end if it was present. On Windows, the default value of HOME is the `Application Data' subdirectory of the user profile directory (normally, this is `C:/Documents and Settings/username/Application Data', where username is your user name), though for backwards compatibility `C:/' will be used instead if a `.emacs' file is found there.

HOSTNAME

The name of the machine that Emacs is running on.

INCPATH

A colon-separated list of directories. Used by the complete package to search for files.

INFOPATH

A colon-separated list of directories in which to search for Info files.

LC_ALL

LC_COLLATE

LC_CTYPE

LC_MESSAGES

LC_MONETARY

LC_NUMERIC

LC_TIME

LANG

The user's preferred locale. The locale has six categories, specified by the environment variables LC_COLLATE for sorting, LC_CTYPE for character encoding, LC_MESSAGES for system messages, LC_MONETARY for monetary formats, LC_NUMERIC for numbers, and LC_TIME for dates and times. If one of these variables is not set, the category defaults to the value of the LANG environment variable, or to the default `C' locale if LANG is not set. But if LC_ALL is specified, it overrides the settings of all the other locale environment variables.

On MS-Windows, if LANG is not already set in the environment when Emacs starts, Emacs sets it based on the system-wide default language, which you can set in the `Regional Settings' Control Panel on some versions of MS-Windows.

The value of the LC_CTYPE category is matched against entries in locale-language-names, locale-charset-language-names, and locale-preferred-coding-systems, to select a default language environment and coding system. See section Language Environments.

LOGNAME

The user's login name. See also USER.

MAIL

The name of your system mail inbox.

MH

Name of setup file for the mh system. (The default is `~/.mh_profile'.)

NAME

Your real-world name.

NNTPSERVER

The name of the news server. Used by the mh and Gnus packages.

ORGANIZATION

The name of the organization to which you belong. Used for setting the `Organization:' header in your posts from the Gnus package.

PATH

A colon-separated list of directories in which executables reside. This is used to initialize the Emacs Lisp variable exec-path.

PWD

If set, this should be the default directory when Emacs was started.

REPLYTO

If set, this specifies an initial value for the variable mail-default-reply-to. See section Mail Header Fields.

SAVEDIR

The name of a directory in which news articles are saved by default. Used by the Gnus package.

SHELL

The name of an interpreter used to parse and execute programs run from inside Emacs.

SMTPSERVER

The name of the outgoing mail server. Used by the SMTP library (see (smtpmail)Top section `Top' in Sending mail via SMTP).

TERM

The type of the terminal that Emacs is using. This variable must be set unless Emacs is run in batch mode. On MS-DOS, it defaults to `internal', which specifies a built-in terminal emulation that handles the machine's own display. If the value of TERM indicates that Emacs runs in non-windowed mode from xterm or a similar terminal emulator, the background mode defaults to `light', and Emacs will choose colors that are appropriate for a light background.

TERMCAP

The name of the termcap library file describing how to program the terminal specified by the TERM variable. This defaults to `/etc/termcap'.

TMPDIR

Used by the Emerge package as a prefix for temporary files.

TZ

This specifies the current time zone and possibly also daylight saving time information. On MS-DOS, if TZ is not set in the environment when Emacs starts, Emacs defines a default value as appropriate for the country code returned by DOS. On MS-Windows, Emacs does not use TZ at all.

USER

The user's login name. See also LOGNAME. On MS-DOS, this defaults to `root'.

VERSION_CONTROL

Used to initialize the version-control variable (see section Numbered Backups).

C.5.2 Miscellaneous Variables

These variables are used only on particular configurations:

COMSPEC

On MS-DOS and MS-Windows, the name of the command interpreter to use when invoking batch files and commands internal to the shell. On MS-DOS this is also used to make a default value for the SHELL environment variable.

NAME

On MS-DOS, this variable defaults to the value of the USER variable.

TEMP

TMP

On MS-DOS and MS-Windows, these specify the name of the directory for storing temporary files in.

EMACSTEST

On MS-DOS, this specifies a file to use to log the operation of the internal terminal emulator. This feature is useful for submitting bug reports.

EMACSCOLORS

On MS-DOS, this specifies the screen colors. It is useful to set them this way, since otherwise Emacs would display the default colors momentarily when it starts up.

The value of this variable should be the two-character encoding of the foreground (the first character) and the background (the second character) colors of the default face. Each character should be the hexadecimal code for the desired color on a standard PC text-mode display. For example, to get blue text on a light gray background, specify `EMACSCOLORS=17', since 1 is the code of the blue color and 7 is the code of the light gray color.

The PC display usually supports only eight background colors. However, Emacs switches the DOS display to a mode where all 16 colors can be used for the background, so all four bits of the background color are actually used.

WINDOW_GFX

Used when initializing the Sun windows system.

PRELOAD_WINSOCK

On MS-Windows, if you set this variable, Emacs will load and initialize the network library at startup, instead of waiting until the first time it is required.

emacs_dir

On MS-Windows, emacs_dir is a special environment variable, which indicates the full path of the directory in which Emacs is installed. If Emacs is installed in the standard directory structure, it calculates this value automatically. It is not much use setting this variable yourself unless your installation is non-standard, since unlike other environment variables, it will be overridden by Emacs at startup. When setting other environment variables, such as EMACSLOADPATH, you may find it useful to use emacs_dir rather than hard-coding an absolute path. This allows multiple versions of Emacs to share the same environment variable settings, and it allows you to move the Emacs installation directory, without changing any environment or registry settings.

C.5.3 The MS-Windows System Registry

Under MS-Windows, the installation program addpm.exe adds values for emacs_dir, EMACSLOADPATH, EMACSDATA, EMACSPATH, EMACSDOC, SHELL and TERM to the `HKEY_LOCAL_MACHINE' section of the system registry, under `/Software/GNU/Emacs'. It does this because there is no standard place to set environment variables across different versions of Windows. Running addpm.exe is no longer strictly necessary in recent versions of Emacs, but if you are upgrading from an older version, running addpm.exe ensures that you do not have older registry entries from a previous installation, which may not be compatible with the latest version of Emacs.

When Emacs starts, as well as checking the environment, it also checks the System Registry for those variables and for HOME, LANG and PRELOAD_WINSOCK.

To determine the value of those variables, Emacs goes through the following procedure. First, the environment is checked. If the variable is not found there, Emacs looks for registry keys by that name under `/Software/GNU/Emacs'; first in the `HKEY_CURRENT_USER' section of the registry, and if not found there, in the `HKEY_LOCAL_MACHINE' section. Finally, if Emacs still cannot determine the values, compiled-in defaults are used.

In addition to the environment variables above, you can also add many of the settings which on X belong in the `.Xdefaults' file (see section X Options and Resources) to the `/Software/GNU/Emacs' registry key. Settings you add to the `HKEY_LOCAL_MACHINE' section will affect all users of the machine. Settings you add to the `HKEY_CURRENT_USER' section will only affect you, and will override machine wide settings.

C.6 Specifying the Display Name

The environment variable DISPLAY tells all X clients, including Emacs, where to display their windows. Its value is set by default in ordinary circumstances, when you start an X server and run jobs locally. Occasionally you may need to specify the display yourself; for example, if you do a remote login and want to run a client program remotely, displaying on your local screen.

With Emacs, the main reason people change the default display is to let them log into another system, run Emacs on that system, but have the window displayed at their local terminal. You might need to log in to another system because the files you want to edit are there, or because the Emacs executable file you want to run is there.

The syntax of the DISPLAY environment variable is `host:display.screen', where host is the host name of the X Window System server machine, display is an arbitrarily-assigned number that distinguishes your server (X terminal) from other servers on the same machine, and screen is a rarely-used field that allows an X server to control multiple terminal screens. The period and the screen field are optional. If included, screen is usually zero.

For example, if your host is named `glasperle' and your server is the first (or perhaps the only) server listed in the configuration, your DISPLAY is `glasperle:0.0'.

You can specify the display name explicitly when you run Emacs, either by changing the DISPLAY variable, or with the option `-d display' or `--display=display'. Here is an example:

emacs --display=glasperle:0 &

You can inhibit the direct use of the window system and GUI with the `-nw' option. It tells Emacs to display using ordinary ASCII on its controlling terminal. This is also an initial option.

Sometimes, security arrangements prevent a program on a remote system from displaying on your local system. In this case, trying to run Emacs produces messages like this:

Xlib:  connection to "glasperle:0.0" refused by server

You might be able to overcome this problem by using the xhost command on the local system to give permission for access from your remote machine.

C.7 Font Specification Options

By default, Emacs displays text in a twelve point Courier font (when using X). You can specify a different font on your command line through the option `-fn name' (or `--font', which is an alias for `-fn').

` -fn name'

` --font=name'

Use font name as the default font.

Under X, each font has a long name which consists of fourteen words or numbers, separated by dashes. Some fonts also have shorter nicknames. For instance, `9x15' is such a nickname. This font makes each character nine pixels wide and fifteen pixels high. You can use either kind of name. Case is insignificant in both kinds. You can use wildcard patterns for the font name; then Emacs lets X choose one of the fonts that match the pattern. The wildcard character `*' matches any sequence of characters (including none) and `?' matches any single character. However, matching is implementation-dependent, and can be inaccurate when wildcards match dashes in a long name. For reliable results, supply all 14 dashes and use wildcards only within a field. Here is an example, which happens to specify the font whose nickname is `6x13':

emacs -fn \
  "-misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1" &

You can also specify the font in your `.Xdefaults' file:

emacs.font: -misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1

Note that if you use a wildcard pattern on the command line, you need to enclose it in single or double quotes, to prevent the shell from accidentally expanding it into a list of file names. On the other hand, you should not quote the name in the `.Xdefaults' file.

The default font used by Emacs (under X) is:

-adobe-courier-medium-r-*-*-*-120-*-*-*-*-iso8859-1

A long font name has the following form:

-maker-family-weight-slant-widthtype-style…
…-pixels-height-horiz-vert-spacing-width-registry-encoding

maker

This is the name of the font manufacturer.

family

This is the name of the font family--for example, `courier'.

weight

This is normally `bold', `medium' or `light'. Other words may appear here in some font names.

slant

This is `r' (roman), `i' (italic), `o' (oblique), `ri' (reverse italic), or `ot' (other).

widthtype

This is normally `condensed', `extended', `semicondensed' or `normal'. Other words may appear here in some font names.

style

This is an optional additional style name. Usually it is empty--most long font names have two hyphens in a row at this point.

pixels

This is the font height, in pixels.

height

This is the font height on the screen, measured in tenths of a printer's point--approximately 1/720 of an inch. In other words, it is the point size of the font, times ten. For a given vertical resolution, height and pixels are proportional; therefore, it is common to specify just one of them and use `*' for the other.

horiz

This is the horizontal resolution, in pixels per inch, of the screen for which the font is intended.

vert

This is the vertical resolution, in pixels per inch, of the screen for which the font is intended. Normally the resolution of the fonts on your system is the right value for your screen; therefore, you normally specify `*' for this and horiz.

spacing

This is `m' (monospace), `p' (proportional) or `c' (character cell).

width

This is the average character width, in pixels, multiplied by ten.

registry

encoding

These together make up the X font character set that the font depicts. (X font character sets are not the same as Emacs charsets, but they are solutions for the same problem.) You can use the xfontsel program to check which choices you have. However, normally you should use `iso8859' for registry and `1' for encoding.

You will probably want to use a fixed-width default font--that is, a font in which all characters have the same width. Any font with `m' or `c' in the spacing field of the long name is a fixed-width font. Here's how to use the xlsfonts program to list all the fixed-width fonts available on your system:

xlsfonts -fn '*x*' | egrep "^[0-9]+x[0-9]+"
xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-m*'
xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-c*'

To see what a particular font looks like, use the xfd command. For example:

xfd -fn 6x13

displays the entire font `6x13'.

While running Emacs, you can set the font of the current frame (see section Setting Frame Parameters) or for a specific kind of text (see section Using Multiple Typefaces).

C.8 Window Color Options

On a color display, you can specify which color to use for various parts of the Emacs display. To find out what colors are available on your system, type M-x list-colors-display, or press C-Mouse-2 and select `Display Colors' from the pop-up menu. (A particular window system might support many more colors, but the list displayed by list-colors-display shows their portable subset that can be safely used on any display supported by Emacs.) If you do not specify colors, on windowed displays the default for the background is white and the default for all other colors is black. On a monochrome display, the foreground is black, the background is white, and the border is gray if the display supports that. On terminals, the background is usually black and the foreground is white.

Here is a list of the command-line options for specifying colors:

` -fg color'

` --foreground-color=color'

Specify the foreground color. color should be a standard color name, or a numeric specification of the color's red, green, and blue components as in `#4682B4' or `RGB:46/82/B4'.

` -bg color'

` --background-color=color'

Specify the background color.

` -bd color'

` --border-color=color'

Specify the color of the border of the X window.

` -cr color'

` --cursor-color=color'

Specify the color of the Emacs cursor which indicates where point is.

` -ms color'

` --mouse-color=color'

Specify the color for the mouse cursor when the mouse is in the Emacs window.

` -r'

` -rv'

` --reverse-video'

Reverse video--swap the foreground and background colors.

` --color=mode'

For a character terminal only, specify the mode of color support. This option is intended for overriding the number of supported colors that the character terminal advertises in its termcap or terminfo database. The parameter mode can be one of the following:

` never'

` no'

Don't use colors even if the terminal's capabilities specify color support.

` default'

` auto'

Same as when `--color' is not used at all: Emacs detects at startup whether the terminal supports colors, and if it does, turns on colored display.

` always'

` yes'

` ansi8'

Turn on the color support unconditionally, and use color commands specified by the ANSI escape sequences for the 8 standard colors.

` num'

Use color mode for num colors. If num is -1, turn off color support (equivalent to `never'); if it is 0, use the default color support for this terminal (equivalent to `auto'); otherwise use an appropriate standard mode for num colors. Depending on your terminal's capabilities, Emacs might be able to turn on a color mode for 8, 16, 88, or 256 as the value of num. If there is no mode that supports num colors, Emacs acts as if num were 0, i.e. it uses the terminal's default color support mode.

If mode is omitted, it defaults to ansi8.

For example, to use a coral mouse cursor and a slate blue text cursor, enter:

emacs -ms coral -cr 'slate blue' &

You can reverse the foreground and background colors through the `-rv' option or with the X resource `reverseVideo'.

The `-fg', `-bg', and `-rv' options function on text-only terminals as well as on graphical displays.

C.9 Options for Window Size and Position

Here is a list of the command-line options for specifying size and position of the initial Emacs frame:

` -g widthxheight[{+-}xoffset{+-}yoffset]]'

` --geometry=widthxheight[{+-}xoffset{+-}yoffset]]'

Specify the size width and height (measured in character columns and lines), and positions xoffset and yoffset (measured in pixels). The width and height parameters apply to all frames, whereas xoffset and yoffset only to the initial frame.

` -fs'

` --fullscreen'

Specify that width and height shall be the size of the screen.

` -fh'

` --fullheight'

Specify that the height shall be the height of the screen.

` -fw'

` --fullwidth'

Specify that the width shall be the width of the screen.

In the `--geometry' option, {+-} means either a plus sign or a minus sign. A plus sign before xoffset means it is the distance from the left side of the screen; a minus sign means it counts from the right side. A plus sign before yoffset means it is the distance from the top of the screen, and a minus sign there indicates the distance from the bottom. The values xoffset and yoffset may themselves be positive or negative, but that doesn't change their meaning, only their direction.

Emacs uses the same units as xterm does to interpret the geometry. The width and height are measured in characters, so a large font creates a larger frame than a small font. (If you specify a proportional font, Emacs uses its maximum bounds width as the width unit.) The xoffset and yoffset are measured in pixels.

You do not have to specify all of the fields in the geometry specification. If you omit both xoffset and yoffset, the window manager decides where to put the Emacs frame, possibly by letting you place it with the mouse. For example, `164x55' specifies a window 164 columns wide, enough for two ordinary width windows side by side, and 55 lines tall.

The default width for Emacs is 80 characters and the default height is 40 lines. You can omit either the width or the height or both. If you start the geometry with an integer, Emacs interprets it as the width. If you start with an `x' followed by an integer, Emacs interprets it as the height. Thus, `81' specifies just the width; `x45' specifies just the height.

If you start with `+' or `-', that introduces an offset, which means both sizes are omitted. Thus, `-3' specifies the xoffset only. (If you give just one offset, it is always xoffset.) `+3-3' specifies both the xoffset and the yoffset, placing the frame near the bottom left of the screen.

You can specify a default for any or all of the fields in `.Xdefaults' file, and then override selected fields with a `--geometry' option.

Since the mode line and the echo area occupy the last 2 lines of the frame, the height of the initial text window is 2 less than the height specified in your geometry. In non-X-toolkit versions of Emacs, the menu bar also takes one line of the specified number. But in the X toolkit version, the menu bar is additional and does not count against the specified height. The tool bar, if present, is also additional.

Enabling or disabling the menu bar or tool bar alters the amount of space available for ordinary text. Therefore, if Emacs starts up with a tool bar (which is the default), and handles the geometry specification assuming there is a tool bar, and then your `~/.emacs' file disables the tool bar, you will end up with a frame geometry different from what you asked for. To get the intended size with no tool bar, use an X resource to specify "no tool bar" (see section Table of X Resources for Emacs); then Emacs will already know there's no tool bar when it processes the specified geometry.

When using one of `--fullscreen', `--fullwidth' or `--fullheight' there may be some space around the frame anyway. That is because Emacs rounds the sizes so they are an even number of character heights and widths.

Some window managers have options that can make them ignore both program-specified and user-specified positions (sawfish is one). If these are set, Emacs fails to position the window correctly.

C.10 Internal and External Borders

An Emacs frame has an internal border and an external border. The internal border is an extra strip of the background color around the text portion of the frame. Emacs itself draws the internal border. The external border is added by the window manager outside the frame; depending on the window manager you use, it may contain various boxes you can click on to move or iconify the window.

` -ib width'

` --internal-border=width'

Specify width as the width of the internal border (between the text and the main border), in pixels.

` -bw width'

` --border-width=width'

Specify width as the width of the main border, in pixels.

When you specify the size of the frame, that does not count the borders. The frame's position is measured from the outside edge of the external border.

Use the `-ib n' option to specify an internal border n pixels wide. The default is 1. Use `-bw n' to specify the width of the external border (though the window manager may not pay attention to what you specify). The default width of the external border is 2.

C.11 Frame Titles

An Emacs frame may or may not have a specified title. The frame title, if specified, appears in window decorations and icons as the name of the frame. If an Emacs frame has no specified title, the default title has the form `invocation-name@machine' (if there is only one frame) or the selected window's buffer name (if there is more than one frame).

You can specify a title for the initial Emacs frame with a command line option:

` -T title'

` --title=title'

Specify title as the title for the initial Emacs frame.

The `--name' option (see section X Resources) also specifies the title for the initial Emacs frame.

C.12 Icons

Most window managers allow you to "iconify" a frame, removing it from sight, and leaving a small, distinctive "icon" window in its place. Clicking on the icon window makes the frame itself appear again. If you have many clients running at once, you can avoid cluttering up the screen by iconifying most of the clients.

` -nbi'

` --no-bitmap-icon'

Do not use a picture of a gnu as the Emacs icon.

` -iconic'

` --iconic'

Start Emacs in iconified state.

By default Emacs uses an icon window containing a picture of the GNU gnu. The `-nbi' or `--no-bitmap-icon' option tells Emacs to let the window manager choose what sort of icon to use--usually just a small rectangle containing the frame's title.

The `-iconic' option tells Emacs to begin running as an icon, rather than showing a frame right away. In this situation, the icon is the only indication that Emacs has started; the text frame doesn't appear until you deiconify it.

C.13 Other Display Options

` -hb'

` --horizontal-scroll-bars'

Enable horizontal scroll bars. Since horizontal scroll bars are not yet implemented, this actually does nothing.

` -vb'

` --vertical-scroll-bars'

Enable vertical scroll bars.

` -lsp pixels'

` --line-spacing=pixels'

Specify pixels as additional space to put between lines, in pixels.

` -nbc'

` --no-blinking-cursor'

Disable the blinking cursor on graphical displays.

` -D'

` --basic-display'

Disable the menu-bar, the tool-bar, the scroll-bars, and tool tips, and turn off the blinking cursor. This can be useful for making a test case that simplifies debugging of display problems.

The `--xrm' option (see section X Resources) specifies additional X resource values.

This document was generated by Mark Kaminski on July, 3 2008 using texi2html 1.70.