Here is a table of action arguments:

file, --file=file, --find-file=file, --visit=file

Visit the specified file. Visiting. When Emacs starts up, it displays the startup buffer in one window, and the buffer visiting file in another window (Windows). If you supply more than one file argument, the displayed file is the last one specified on the command line; the other files are visited but their buffers are not shown. If the startup buffer is disabled (Entering Emacs), then starting Emacs with one file argument displays the buffer visiting file in a single window. With two file arguments, Emacs displays the files in two different windows. With more than two file arguments, Emacs displays the last file specified in one window, plus another window with a Buffer Menu showing all the other files (Several Buffers). To inhibit using the Buffer Menu for this, change the variable inhibit-startup-buffer-menu to t.

+linenum file

Visit the specified file, then go to line number linenum in it.

+linenum:columnnum file

Visit the specified 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. If file is not an absolute file name, Emacs first looks for it in the current directory, then in the directories listed in load-path (Lisp Libraries). Warning: If previous command-line arguments have visited files, the current directory is the directory of the last file visited.

-L dir, --directory=dir

Prepend directory dir to the variable load-path. If you specify multiple -L options, Emacs preserves the relative order; i.e., using -L /foo -L /bar results in a load-path of the form ("/foo" "/bar" ...). If dir begins with :, Emacs removes the : and appends (rather than prepends) the remainder to load-path. (On MS Windows, use ; instead of :; i.e., use the value of path-separator.)

-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 buffer that is current when this command-line argument is processed. Usually, this is the *scratch* buffer (Lisp Interaction), but if arguments earlier on the command line visit files or switch buffers, that might be a different buffer. The effect of this command-line argument is like what M-x insert-file does (Misc File Ops).

--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.

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 the initialization file. Normally, Emacs first loads site-start.el if it exists, then your own initialization file if it exists, and finally the default initialization file default.el if it exists (Init File). Certain options prevent loading of some of these files or substitute other files for them.

-chdir directory, --chdir=directory

Change to directory before doing anything else. This is mainly used by session management in X so that Emacs starts in the same directory as it stopped. This makes desktop saving and restoring easier.

-t device, --terminal=device

Use device as the device for terminal input and output. This option 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. Display X, 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. To invoke a Lisp program, use the -batch option in conjunction with one or more of -l, -f or --eval (Action Arguments). Command Example, for an example. In batch mode, Emacs does not display the text being edited, and the standard terminal interrupt characters such as C-z and C-c have their usual effect. Emacs functions that normally print a message in the echo area will print to either the standard output stream (stdout) or the standard error stream (stderr) instead. (To be precise, functions like prin1, princ and print print to stdout, while message and error print to stderr.) Functions that normally read keyboard input from the minibuffer take their input from the terminal's standard input stream (stdin) instead. --batch implies -q (do not load an initialization 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 auto-saving is explicitly requested, and when saving files it omits the fsync system call unless otherwise requested. Errors that occur when running a --batch Emacs will result in an Emacs Lisp backtrace being printed. To disable this behavior, set backtrace-on-error-noninteractive to nil.

--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 the #! on this first line as a comment delimiter.

--no-build-details

Omit details like system name and build time from the Emacs executable, so that builds are more deterministic. This switch is not meant for regular (or interactive) use, since it makes commands like system-name return nil.

-q, --no-init-file

Do not load any initialization file (Init File). When Emacs is invoked with this option, the Customize facility does not allow options to be saved (Easy Customization). This option does not disable loading site-start.el.

--no-site-file, -nsl

Do not load site-start.el (Init File). The -Q option does this too, but other options like -q do not.

--no-site-lisp

Do not include the site-lisp directories in load-path (Init File). The -Q option does this too.

--no-splash

Do not display a startup screen. You can also achieve this effect by setting the variable inhibit-startup-screen to non-nil in your initialization file (Entering Emacs).

--no-x-resources

Do not load X resources. You can also achieve this effect by setting the variable inhibit-x-resources to t in your initialization file (Resources).

-Q, --quick

Start Emacs with minimum customizations. This is similar to using -q, --no-site-file, --no-site-lisp, --no-x-resources, and --no-splash together.

-daemon, --daemon[=name], --bg-daemon[=name], --fg-daemon[=name]

Start Emacs as a daemon: after Emacs starts up, it starts the Emacs server without opening any frames. You can then use the emacsclient command to connect to Emacs for editing. (Optionally, you can specify an explicit name for the server; if you do, you will need to specify the same name when you invoke emacsclient, via its --socket-name option, see emacsclient Options.) Emacs Server, for information about using Emacs as a daemon. A "background" daemon disconnects from the terminal and runs in the background (--daemon is an alias for --bg-daemon).

--no-desktop

Do not reload any saved desktop. Saving Emacs Sessions.

-u user, --user=user

Load user's initialization file instead of your own(This option has no effect on MS-Windows.).

--debug-init

Enable the Emacs Lisp debugger for errors in the init file. Entering the Debugger on an Error.

--module-assertions

Enable expensive correctness checks when dealing with dynamically loadable modules. This is intended for module authors that wish to verify that their module conforms to the module API requirements. The option makes Emacs abort if a module-related assertion triggers. Writing Dynamically-Loaded Modules.

--dump-file=file

Load the dumped Emacs state from the named file. By default, an installed Emacs will look for its dump state in a file named emacs.pdmp in the directory where the Emacs installation puts the architecture-dependent files; the variable exec-directory holds the name of that directory. emacs is the name of the Emacs executable file, normally just emacs. (When you invoke Emacs from the src directory where it was built without installing it, it will look for the dump file in the directory of the executable.) If you rename or move the dump file to a different place, you can use this option to tell Emacs where to find that file.

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.

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 programs) inherit the environment from Emacs, too. Inside Emacs, the command M-x getenv reads the name of an environment variable, and prints its value in the echo area. M-x setenv sets a variable in the Emacs environment, and C-u M-x setenv removes a variable. (Environment variable substitutions with $ work in the value just as in file names; see File Names with $.) The variable initial-environment stores the initial environment inherited by Emacs. 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.

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. You can specify the display yourself; one reason to do this is if you want to log into another system and run Emacs there, and have the window displayed at your local terminal. DISPLAY has the syntax /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 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 use of the X window system with the -nw option. Then Emacs uses its controlling text terminal for display. Initial Options. 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.

You can use the command line option -fn /font/ (or --font, which is an alias for -fn) to specify a default font:

-fn font, --font=font

Use font as the default font.

When passing a font name to Emacs on the command line, you may need to quote it, by enclosing it in quotation marks, if it contains characters that the shell treats specially (e.g., spaces). For example:

emacs -fn "DejaVu Sans Mono-12"

Fonts, for details about font names and other ways to specify the default font.

You can use the following command-line options to specify the colors to use for various parts of the Emacs display. Colors may be specified using either color names or RGB triplets (Colors).

-fg color, --foreground-color=color

Specify the foreground color, overriding the color specified by the default face (Faces).

-bg color, --background-color=color

Specify the background color, overriding the color specified by the default face.

-bd color, --border-color=color

Specify the color of the border of the X window. This has no effect if Emacs is compiled with GTK+ support.

-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

Set the color support mode when Emacs is run on a text terminal. This option overrides 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 terminals as well as on graphical displays.

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 should be that of the screen. Normally no window manager decorations are shown. (After starting Emacs, you can toggle this state using F11, toggle-frame-fullscreen.)

-mm, --maximized

Specify that the Emacs frame should be maximized. This normally means that the frame has window manager decorations. (After starting Emacs, you can toggle this state using M-F10, toggle-frame-maximized.)

-fh, --fullheight

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

-fw, --fullwidth

Specify that the width should 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 frame width is 80 characters and the default height is between 35 and 40 lines, depending on the OS and the window manager. 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 the geometry 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 your X resource file (Resources), 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 initialization 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" (Table of Resources); then Emacs will already know there's no tool bar when it processes the specified geometry. When using one of --fullscreen, --maximized, --fullwidth or --fullheight, some window managers require you to set the variable frame-resize-pixelwise to a non-nil value to make a frame appear truly maximized or full-screen. Some window managers have options that can make them ignore both program-specified and user-specified positions. If these are set, Emacs fails to position the window correctly.

An Emacs frame has an internal border and an outer 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 outer border is drawn by X outside the tool and menu bars of the frame. There is also an external border which is drawn by the window manager. The size of the external border cannot be set from within Emacs.

-ib width, --internal-border=width

Specify width as the width of the internal border (around the frame's text area), in pixels.

-bw width, --border-width=width

Specify width as the width of the outer 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 outer border (though the window manager may not pay attention to what you specify). The default width of the outer border is 2.

Each Emacs frame always has a title, which appears in window decorations and icons as the name of the frame. The default title is of the form /invocation-name/@@/machine/ (if there is only one frame) or shows the selected window's buffer name (if there is more than one frame). You can specify a non-default 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 (Resources) also specifies the title for the initial Emacs frame.

-iconic, --iconic

Start Emacs in an iconified state.

-nbi, --no-bitmap-icon

Disable the use of the Emacs icon.

Most window managers allow you to iconify (or "minimize") an Emacs frame, hiding it from sight. Some window managers replace iconified windows with tiny icons, while others remove them entirely from sight. The -iconic option tells Emacs to begin running in an iconified state, rather than showing a frame right away. The text frame doesn't appear until you deiconify (or "un-minimize") it. By default, Emacs uses an icon containing the Emacs logo. On desktop environments such as Gnome, this icon is also displayed in other contexts, e.g., when switching into an Emacs frame. 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.

--parent-id id

Open Emacs as a client X window via the XEmbed protocol, with id as the parent X window id. Currently, this option is mainly useful for developers.

-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, tool tips, and turn off font-lock-mode and the blinking cursor. This can be useful for making a test case that simplifies debugging of display problems.

The --xrm option (Resources) specifies additional X resource values.