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6bf7aab6 1@c This is part of the Emacs manual.
739a80b3 2@c Copyright (C) 1985,86,87,93,94,95,1997,2001 Free Software Foundation, Inc.
6bf7aab6 3@c See file emacs.texi for copying conditions.
21af0bfa 4@node Command Arguments, X Resources, Service, Top
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5@appendix Command Line Arguments
6@cindex command line arguments
7@cindex arguments (command line)
8@cindex options (command line)
9@cindex switches (command line)
10@cindex startup (command line arguments)
11
12 GNU Emacs supports command line arguments to request various actions
13when invoking Emacs. These are for compatibility with other editors and
14for sophisticated activities. We don't recommend using them for
15ordinary editing.
16
17 Arguments starting with @samp{-} are @dfn{options}. Other arguments
18specify files to visit. Emacs visits the specified files while it
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19starts up. The last file name on your command line becomes the
20current buffer; the other files are also visited in other buffers. If
21there are two files, they are both displayed; otherwise the last file
22is displayed along with a buffer list that shows what other buffers
23there are. As with most programs, the special argument @samp{--} says
24that all subsequent arguments are file names, not options, even if
25they start with @samp{-}.
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26
27 Emacs command options can specify many things, such as the size and
28position of the X window Emacs uses, its colors, and so on. A few
29options support advanced usage, such as running Lisp functions on files
30in batch mode. The sections of this chapter describe the available
31options, arranged according to their purpose.
32
33 There are two ways of writing options: the short forms that start with
34a single @samp{-}, and the long forms that start with @samp{--}. For
35example, @samp{-d} is a short form and @samp{--display} is the
36corresponding long form.
37
38 The long forms with @samp{--} are easier to remember, but longer to
39type. However, you don't have to spell out the whole option name; any
40unambiguous abbreviation is enough. When a long option takes an
41argument, you can use either a space or an equal sign to separate the
42option name and the argument. Thus, you can write either
43@samp{--display sugar-bombs:0.0} or @samp{--display=sugar-bombs:0.0}.
44We recommend an equal sign because it makes the relationship clearer,
45and the tables below always show an equal sign.
46
47@cindex initial options (command line)
48@cindex action options (command line)
49 Most options specify how to initialize Emacs, or set parameters for
50the Emacs session. We call them @dfn{initial options}. A few options
51specify things to do: for example, load libraries, call functions, or
0ec1f115 52terminate Emacs. These are called @dfn{action options}. These and file
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53names together are called @dfn{action arguments}. Emacs processes all
54the action arguments in the order they are written.
55
56@menu
57* Action Arguments:: Arguments to visit files, load libraries,
58 and call functions.
59* Initial Options:: Arguments that take effect while starting Emacs.
60* Command Example:: Examples of using command line arguments.
61* Resume Arguments:: Specifying arguments when you resume a running Emacs.
62* Environment:: Environment variables that Emacs uses.
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63* Display X:: Changing the default display and using remote login.
64* Font X:: Choosing a font for text, under X.
e15044ea 65* Colors:: Choosing display colors.
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66* Window Size X:: Start-up window size, under X.
67* Borders X:: Internal and external borders, under X.
68* Title X:: Specifying the initial frame's title.
69* Icons X:: Choosing what sort of icon to use, under X.
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70@end menu
71
72@node Action Arguments
73@appendixsec Action Arguments
74
75 Here is a table of the action arguments and options:
76
77@table @samp
78@item @var{file}
a8575fe5 79@opindex --visit
ec22060b 80@itemx --visit=@var{file}
a8575fe5 81@opindex --file
ec22060b 82@itemx --file=@var{file}
a8575fe5 83@cindex visiting files, command-line argument
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84Visit @var{file} using @code{find-file}. @xref{Visiting}.
85
86@item +@var{linenum} @var{file}
a8575fe5 87@opindex +@var{linenum}
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88Visit @var{file} using @code{find-file}, then go to line number
89@var{linenum} in it.
90
660872b6 91@item +@var{linenum}:@var{columnnum} @var{file}
660872b6 92Visit @var{file} using @code{find-file}, then go to line number
0ec1f115 93@var{linenum} and put point at column number @var{columnnum}.
660872b6 94
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95@need 3000
96@item -l @var{file}
a8575fe5 97@opindex -l
6bf7aab6 98@itemx --load=@var{file}
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99@opindex --load
100@cindex loading Lisp libraries, command-line argument
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101Load a Lisp library named @var{file} with the function @code{load}.
102@xref{Lisp Libraries}. The library can be found either in the current
103directory, or in the Emacs library search path as specified
60a96371 104with @env{EMACSLOADPATH} (@pxref{General Variables}).
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105
106@item -f @var{function}
a8575fe5 107@opindex -f
6bf7aab6 108@itemx --funcall=@var{function}
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109@opindex --funcall
110@cindex call Lisp functions, command-line argument
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111Call Lisp function @var{function} with no arguments.
112
ec22060b 113@item --eval=@var{expression}
a8575fe5 114@opindex --eval
ec22060b 115@itemx --execute=@var{expression}
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116@opindex --execute
117@cindex evaluate expression, command-line argument
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118Evaluate Lisp expression @var{expression}.
119
120@item --insert=@var{file}
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121@opindex --insert
122@cindex insert file contents, command-line argument
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123Insert the contents of @var{file} into the current buffer. This is like
124what @kbd{M-x insert-file} does. @xref{Misc File Ops}.
125
126@item --kill
a8575fe5 127@opindex --kill
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128Exit from Emacs without asking for confirmation.
129@end table
130
131@vindex command-line-args
132 The init file can access the values of the action arguments as the
133elements of a list in the variable @code{command-line-args}. The init
134file can override the normal processing of the action arguments, or
135define new ones, by reading and setting this variable.
136
137@node Initial Options
138@appendixsec Initial Options
139
140 The initial options specify parameters for the Emacs session. This
141section describes the more general initial options; some other options
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142specifically related to the X Window System appear in the following
143sections.
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144
145 Some initial options affect the loading of init files. The normal
146actions of Emacs are to first load @file{site-start.el} if it exists,
147then your own init file @file{~/.emacs} if it exists, and finally
148@file{default.el} if it exists; certain options prevent loading of some
149of these files or substitute other files for them.
150
151@table @samp
152@item -t @var{device}
a8575fe5 153@opindex -t
6bf7aab6 154@itemx --terminal=@var{device}
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155@opindex --terminal
156@cindex device for Emacs terminal I/O
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157Use @var{device} as the device for terminal input and output.
158
159@item -d @var{display}
a8575fe5 160@opindex -d
6bf7aab6 161@itemx --display=@var{display}
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162@opindex --display
163@cindex display for Emacs frame
6bf7aab6 164Use the X Window System and use the display named @var{display} to open
a8575fe5 165the initial Emacs frame. @xref{Display X}, for more details.
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166
167@item -nw
a8575fe5 168@opindex -nw
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169@itemx --no-window-system
170@opindex --no-window-system
a8575fe5 171@cindex disable window system
54e33bb3 172Don't communicate directly with the window system, disregarding the
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173@env{DISPLAY} environment variable even if it is set. This means that
174Emacs uses the terminal from which it was launched for all its display
175and input.
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176
177@need 3000
178@cindex batch mode
179@item -batch
a8575fe5 180@opindex --batch
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181@itemx --batch
182Run Emacs in @dfn{batch mode}, which means that the text being edited is
183not displayed and the standard terminal interrupt characters such as
184@kbd{C-z} and @kbd{C-c} continue to have their normal effect. Emacs in
1ba2ce68 185batch mode outputs to @code{stderr} only what would normally be displayed
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186in the echo area under program control, and functions which would
187normally read from the minibuffer take their input from @code{stdin}.
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188
189Batch mode is used for running programs written in Emacs Lisp from
190shell scripts, makefiles, and so on. Normally the @samp{-l} option
191or @samp{-f} option will be used as well, to invoke a Lisp program
192to do the batch processing.
193
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194@samp{-batch} implies @samp{-q} (do not load an init file). It also
195causes Emacs to exit after processing all the command options. In
196addition, it disables auto-saving except in buffers for which it has
197been explicitly requested.
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198
199@item -q
a8575fe5 200@opindex -q
6bf7aab6 201@itemx --no-init-file
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202@opindex --no-init-file
203@cindex bypassing init and site-start file
204@cindex init file, not loading
3b703ce9 205@cindex @file{default.el} file, not loading
6bf7aab6 206Do not load your Emacs init file @file{~/.emacs}, or @file{default.el}
21742660 207either. When invoked like this, Emacs does not allow saving options
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208changed with the @kbd{M-x customize} command and its variants.
209@xref{Easy Customization}.
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210
211@item --no-site-file
a8575fe5 212@opindex --no-site-file
3b703ce9 213@cindex @file{site-start.el} file, not loading
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214Do not load @file{site-start.el}. The options @samp{-q}, @samp{-u}
215and @samp{-batch} have no effect on the loading of this file---this is
216the only option that blocks it.
217
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218@item --no-splash
219@opindex --no-splash
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220@vindex inhibit-startup-message
221Do not display a splash screen on startup; this is equivlaent to
222setting the variable @code{inhibit-startup-message} to non-nil.
223
6bf7aab6 224@item -u @var{user}
a8575fe5 225@opindex -u
6bf7aab6 226@itemx --user=@var{user}
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227@opindex --user
228@cindex load init file of another user
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229Load @var{user}'s Emacs init file @file{~@var{user}/.emacs} instead of
230your own.
231
232@item --debug-init
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233@opindex --debug-init
234@cindex errors in init file
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235Enable the Emacs Lisp debugger for errors in the init file.
236
237@item --unibyte
a8575fe5 238@opindex --unibyte
56bfaffd 239@cindex unibyte operation, command-line argument
1a1b17bc 240Do almost everything with single-byte buffers and strings.
6bf7aab6 241All buffers and strings are unibyte unless you (or a Lisp program)
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242explicitly ask for a multibyte buffer or string. (Note that Emacs
243always loads Lisp files in multibyte mode, even if @samp{--unibyte} is
244specified; see @ref{Enabling Multibyte}.) Setting the environment
245variable @env{EMACS_UNIBYTE} has the same effect.
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246
247@item --multibyte
a8575fe5 248@opindex --multibyte
60a96371 249Inhibit the effect of @env{EMACS_UNIBYTE}, so that Emacs
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250uses multibyte characters by default, as usual.
251@end table
252
253@node Command Example
254@appendixsec Command Argument Example
255
256 Here is an example of using Emacs with arguments and options. It
257assumes you have a Lisp program file called @file{hack-c.el} which, when
258loaded, performs some useful operation on the current buffer, expected
259to be a C program.
260
261@example
262emacs -batch foo.c -l hack-c -f save-buffer >& log
263@end example
264
265@noindent
266This says to visit @file{foo.c}, load @file{hack-c.el} (which makes
267changes in the visited file), save @file{foo.c} (note that
268@code{save-buffer} is the function that @kbd{C-x C-s} is bound to), and
269then exit back to the shell (because of @samp{-batch}). @samp{-batch}
270also guarantees there will be no problem redirecting output to
271@file{log}, because Emacs will not assume that it has a display terminal
272to work with.
273
274@node Resume Arguments
275@appendixsec Resuming Emacs with Arguments
276
277 You can specify action arguments for Emacs when you resume it after
278a suspension. To prepare for this, put the following code in your
279@file{.emacs} file (@pxref{Hooks}):
280
515d3b4b 281@c `resume-suspend-hook' is correct. It is the name of a function.
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282@example
283(add-hook 'suspend-hook 'resume-suspend-hook)
284(add-hook 'suspend-resume-hook 'resume-process-args)
285@end example
286
287 As further preparation, you must execute the shell script
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288@file{emacs.csh} (if you use csh as your shell) or @file{emacs.bash}
289(if you use bash as your shell). These scripts define an alias named
6bf7aab6 290@code{edit}, which will resume Emacs giving it new command line
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291arguments such as files to visit. The scripts are found in the
292@file{etc} subdirectory of the Emacs distribution.
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293
294 Only action arguments work properly when you resume Emacs. Initial
295arguments are not recognized---it's too late to execute them anyway.
296
297 Note that resuming Emacs (with or without arguments) must be done from
298within the shell that is the parent of the Emacs job. This is why
299@code{edit} is an alias rather than a program or a shell script. It is
300not possible to implement a resumption command that could be run from
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301other subjobs of the shell; there is no way to define a command that could
302be made the value of @env{EDITOR}, for example. Therefore, this feature
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303does not take the place of the Emacs Server feature (@pxref{Emacs
304Server}).
305
306 The aliases use the Emacs Server feature if you appear to have a
307server Emacs running. However, they cannot determine this with complete
308accuracy. They may think that a server is still running when in
309actuality you have killed that Emacs, because the file
515d3b4b 310@file{/tmp/esrv@dots{}} still exists. If this happens, find that
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311file and delete it.
312
313@node Environment
314@appendixsec Environment Variables
315@cindex environment variables
316
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317 The @dfn{environment} is a feature of the operating system; it
318consists of a collection of variables with names and values. Each
319variable is called an @dfn{environment variable}; environment variable
320names are case-sensitive, and it is conventional to use upper case
321letters only. The values are all text strings.
6bf7aab6 322
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323 What makes the environment useful is that subprocesses inherit the
324environment automatically from their parent process. This means you
325can set up an environment variable in your login shell, and all the
326programs you run (including Emacs) will automatically see it.
327Subprocesses of Emacs (such as shells, compilers, and version-control
328software) inherit the environment from Emacs, too.
329
330@findex setenv
331@findex getenv
332 Inside Emacs, the command @kbd{M-x getenv} gets the value of an
333environment variable. @kbd{M-x setenv} sets a variable in the Emacs
334environment. The way to set environment variables outside of Emacs
335depends on the operating system, and especially the shell that you are
336using. For example, here's how to set the environment variable
337@env{ORGANIZATION} to @samp{not very much} using Bash:
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338
339@example
340export ORGANIZATION="not very much"
341@end example
342
343@noindent
344and here's how to do it in csh or tcsh:
345
346@example
347setenv ORGANIZATION "not very much"
348@end example
349
1a1b17bc 350 When Emacs is uses the X Window System, it inherits the use
4b1ad19a 351of a large number of environment variables from the X libraries. See
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352the X documentation for more information.
353
354@menu
355* General Variables:: Environment variables that all versions of Emacs use.
356* Misc Variables:: Certain system-specific variables.
357@end menu
358
359@node General Variables
360@appendixsubsec General Variables
361
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362 Here is an alphabetical list of specific environment variables that
363have special meanings in Emacs, giving the name of each variable and
364its meaning. Most of these variables are also used by some other
365programs. Emacs does not require any of these environment variables
366to be set, but it uses their values if they are set.
367
60a96371 368@table @env
f51e949c 369@item CDPATH
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370Used by the @code{cd} command to search for the directory you specify,
371when you specify a relative directory name.
6bf7aab6 372@item EMACS_UNIBYTE
56bfaffd 373@cindex unibyte operation, environment variable
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374Defining this environment variable with a nonempty value directs Emacs
375to do almost everything with single-byte buffers and strings. It is
376equivalent to using the @samp{--unibyte} command-line option on each
377invocation. @xref{Initial Options}.
6bf7aab6 378@item EMACSDATA
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379Directory for the architecture-independent files that come with Emacs.
380This is used to initialize the Lisp variable @code{data-directory}.
18a349f5 381@item EMACSDOC
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382Directory for the documentation string file,
383@file{DOC-@var{emacsversion}}. This is used to initialize the Lisp
b389557a 384variable @code{doc-directory}.
6bf7aab6 385@item EMACSLOADPATH
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386A colon-separated list of directories@footnote{
387Here and below, whenever we say ``colon-separated list of directories'',
388it pertains to Unix and GNU/Linux systems. On MS-DOS and MS-Windows,
389the directories are separated by semi-colons instead, since DOS/Windows
390file names might include a colon after a drive letter.}
391to search for Emacs Lisp files---used to initialize @code{load-path}.
6bf7aab6 392@item EMACSPATH
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393A colon-separated list of directories to search for executable
394files---used to initialize @code{exec-path}.
6bf7aab6 395@item ESHELL
60a96371 396Used for shell-mode to override the @env{SHELL} environment variable.
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397@item HISTFILE
398The name of the file that shell commands are saved in between logins.
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399This variable defaults to @file{~/.bash_history} if you use Bash, to
400@file{~/.sh_history} if you use ksh, and to @file{~/.history}
401otherwise.
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402@item HOME
403The location of the user's files in the directory tree; used for
404expansion of file names starting with a tilde (@file{~}). On MS-DOS, it
405defaults to the directory from which Emacs was started, with @samp{/bin}
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406removed from the end if it was present. On Windows, the default value
407of @code{HOME} is @file{C:/}, the root directory of drive @file{C:}.
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408@item HOSTNAME
409The name of the machine that Emacs is running on.
410@item INCPATH
411A colon-separated list of directories. Used by the @code{complete} package
412to search for files.
413@item INFOPATH
b389557a 414A colon-separated list of directories in which to search for Info files.
fbc164de 415@item LC_ALL
9c6251b6 416@itemx LC_COLLATE
6bf7aab6 417@itemx LC_CTYPE
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418@itemx LC_MESSAGES
419@itemx LC_MONETARY
420@itemx LC_NUMERIC
421@itemx LC_TIME
fbc164de 422@itemx LANG
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423The user's preferred locale. The locale has six categories, specified
424by the environment variables @env{LC_COLLATE} for sorting,
425@env{LC_CTYPE} for character encoding, @env{LC_MESSAGES} for system
426messages, @env{LC_MONETARY} for monetary formats, @env{LC_NUMERIC} for
427numbers, and @env{LC_TIME} for dates and times. If one of these
428variables is not set, the category defaults to the value of the
429@env{LANG} environment variable, or to the default @samp{C} locale if
430@env{LANG} is not set. But if @env{LC_ALL} is specified, it overrides
431the settings of all the other locale environment variables.
432
433The value of the LC_CTYPE category is
4b1ad19a 434matched against entries in @code{locale-language-names},
fbc164de 435@code{locale-charset-language-names}, and
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436@code{locale-preferred-coding-systems}, to select a default language
437environment and coding system. @xref{Language Environments}.
6bf7aab6 438@item LOGNAME
60a96371 439The user's login name. See also @env{USER}.
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440@item MAIL
441The name of the user's system mail inbox.
442@item MAILRC
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443Name of file containing mail aliases. (The default is
444@file{~/.mailrc}.)
6bf7aab6 445@item MH
4b1ad19a 446Name of setup file for the mh system. (The default is @file{~/.mh_profile}.)
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447@item NAME
448The real-world name of the user.
449@item NNTPSERVER
5937ea41 450The name of the news server. Used by the mh and Gnus packages.
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451@item ORGANIZATION
452The name of the organization to which you belong. Used for setting the
5937ea41 453`Organization:' header in your posts from the Gnus package.
6bf7aab6 454@item PATH
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455A colon-separated list of directories in which executables reside. This
456is used to initialize the Emacs Lisp variable @code{exec-path}.
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457@item PWD
458If set, this should be the default directory when Emacs was started.
459@item REPLYTO
460If set, this specifies an initial value for the variable
461@code{mail-default-reply-to}. @xref{Mail Headers}.
462@item SAVEDIR
463The name of a directory in which news articles are saved by default.
5937ea41 464Used by the Gnus package.
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465@item SHELL
466The name of an interpreter used to parse and execute programs run from
467inside Emacs.
b370b3b0 468@cindex background mode, on @code{xterm}
6bf7aab6 469@item TERM
0ec1f115 470The type of the terminal that Emacs is using. This variable must be
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471set unless Emacs is run in batch mode. On MS-DOS, it defaults to
472@samp{internal}, which specifies a built-in terminal emulation that
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473handles the machine's own display. If the value of @env{TERM} indicates
474that Emacs runs in non-windowed mode from @code{xterm} or a similar
475terminal emulator, the background mode defaults to @samp{light}, and
476Emacs will choose colors that are appropriate for a light background.
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477@item TERMCAP
478The name of the termcap library file describing how to program the
60a96371 479terminal specified by the @env{TERM} variable. This defaults to
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480@file{/etc/termcap}.
481@item TMPDIR
482Used by the Emerge package as a prefix for temporary files.
483@item TZ
94c3309f 484This specifies the current time zone and possibly also daylight
3e40caf4 485saving time information. On MS-DOS, if @code{TZ} is not set in the
94c3309f 486environment when Emacs starts, Emacs defines a default value as
9c3aede4 487appropriate for the country code returned by DOS. On MS-Windows, Emacs
94c3309f 488does not use @code{TZ} at all.
6bf7aab6 489@item USER
60a96371 490The user's login name. See also @env{LOGNAME}. On MS-DOS, this
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491defaults to @samp{root}.
492@item VERSION_CONTROL
493Used to initialize the @code{version-control} variable (@pxref{Backup
494Names}).
495@end table
496
497@node Misc Variables
498@appendixsubsec Miscellaneous Variables
499
500These variables are used only on particular configurations:
501
60a96371 502@table @env
6bf7aab6 503@item COMSPEC
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504On MS-DOS and MS-Windows, the name of the command interpreter to use
505when invoking batch files and commands internal to the shell. On MS-DOS
506this is also used to make a default value for the @env{SHELL} environment
507variable.
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508
509@item NAME
60a96371 510On MS-DOS, this variable defaults to the value of the @env{USER}
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511variable.
512
513@item TEMP
514@itemx TMP
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515On MS-DOS and MS-Windows, these specify the name of the directory for
516storing temporary files in.
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517
518@item EMACSTEST
519On MS-DOS, this specifies a file to use to log the operation of the
520internal terminal emulator. This feature is useful for submitting bug
521reports.
522
523@item EMACSCOLORS
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524On MS-DOS, this specifies the screen colors. It is useful to set them
525this way, since otherwise Emacs would display the default colors
526momentarily when it starts up.
527
528The value of this variable should be the two-character encoding of the
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529foreground (the first character) and the background (the second
530character) colors of the default face. Each character should be the
531hexadecimal code for the desired color on a standard PC text-mode
47d7776c 532display. For example, to get blue text on a light gray background,
ed50f966 533specify @samp{EMACSCOLORS=17}, since 1 is the code of the blue color and
47d7776c 5347 is the code of the light gray color.
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535
536The PC display usually supports only eight background colors. However,
537Emacs switches the DOS display to a mode where all 16 colors can be used
538for the background, so all four bits of the background color are
539actually used.
540
541@item WINDOW_GFX
542Used when initializing the Sun windows system.
543@end table
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544
545@node Display X
546@appendixsec Specifying the Display Name
547@cindex display name (X Window System)
548@cindex @env{DISPLAY} environment variable
549
550 The environment variable @env{DISPLAY} tells all X clients, including
551Emacs, where to display their windows. Its value is set by default
552in ordinary circumstances, when you start an X server and run jobs
553locally. Occasionally you may need to specify the display yourself; for
554example, if you do a remote login and want to run a client program
555remotely, displaying on your local screen.
556
557 With Emacs, the main reason people change the default display is to
558let them log into another system, run Emacs on that system, but have the
559window displayed at their local terminal. You might need to log in
560to another system because the files you want to edit are there, or
561because the Emacs executable file you want to run is there.
562
563 The syntax of the @env{DISPLAY} environment variable is
564@samp{@var{host}:@var{display}.@var{screen}}, where @var{host} is the
565host name of the X Window System server machine, @var{display} is an
566arbitrarily-assigned number that distinguishes your server (X terminal)
567from other servers on the same machine, and @var{screen} is a
568rarely-used field that allows an X server to control multiple terminal
569screens. The period and the @var{screen} field are optional. If
570included, @var{screen} is usually zero.
571
572 For example, if your host is named @samp{glasperle} and your server is
573the first (or perhaps the only) server listed in the configuration, your
574@env{DISPLAY} is @samp{glasperle:0.0}.
575
576 You can specify the display name explicitly when you run Emacs, either
577by changing the @env{DISPLAY} variable, or with the option @samp{-d
578@var{display}} or @samp{--display=@var{display}}. Here is an example:
579
580@smallexample
581emacs --display=glasperle:0 &
582@end smallexample
583
584 You can inhibit the direct use of the window system and GUI with the
585@samp{-nw} option. It tells Emacs to display using ordinary ASCII on
586its controlling terminal. This is also an initial option.
587
588 Sometimes, security arrangements prevent a program on a remote system
589from displaying on your local system. In this case, trying to run Emacs
590produces messages like this:
591
592@smallexample
593Xlib: connection to "glasperle:0.0" refused by server
594@end smallexample
595
596@noindent
597You might be able to overcome this problem by using the @code{xhost}
598command on the local system to give permission for access from your
599remote machine.
600
601@node Font X
602@appendixsec Font Specification Options
603@cindex font name (X Window System)
604
605 By default, Emacs displays text in the font named @samp{9x15}, which
606makes each character nine pixels wide and fifteen pixels high. You can
607specify a different font on your command line through the option
608@samp{-fn @var{name}} (or @samp{--font}, which is an alias for
609@samp{-fn}).
610
611@table @samp
612@item -fn @var{name}
613@opindex -fn
614@itemx --font=@var{name}
615@opindex --font
616@cindex specify default font from the command line
617Use font @var{name} as the default font.
618@end table
619
620 Under X, each font has a long name which consists of eleven words or
621numbers, separated by dashes. Some fonts also have shorter
622nicknames---@samp{9x15} is such a nickname. You can use either kind of
623name. You can use wildcard patterns for the font name; then Emacs lets
624X choose one of the fonts that match the pattern. Here is an example,
625which happens to specify the font whose nickname is @samp{6x13}:
626
627@smallexample
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628emacs -fn \
629 "-misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1" &
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630@end smallexample
631
632@noindent
633You can also specify the font in your @file{.Xdefaults} file:
634
635@smallexample
636emacs.font: -misc-fixed-medium-r-semicondensed--13-*-*-*-c-60-iso8859-1
637@end smallexample
638
639 A long font name has the following form:
640
641@smallexample
642-@var{maker}-@var{family}-@var{weight}-@var{slant}-@var{widthtype}-@var{style}@dots{}
643@dots{}-@var{pixels}-@var{height}-@var{horiz}-@var{vert}-@var{spacing}-@var{width}-@var{charset}
644@end smallexample
645
646@table @var
647@item maker
648This is the name of the font manufacturer.
649@item family
650This is the name of the font family---for example, @samp{courier}.
651@item weight
652This is normally @samp{bold}, @samp{medium} or @samp{light}. Other
653words may appear here in some font names.
654@item slant
655This is @samp{r} (roman), @samp{i} (italic), @samp{o} (oblique),
656@samp{ri} (reverse italic), or @samp{ot} (other).
657@item widthtype
658This is normally @samp{condensed}, @samp{extended}, @samp{semicondensed}
659or @samp{normal}. Other words may appear here in some font names.
660@item style
661This is an optional additional style name. Usually it is empty---most
662long font names have two hyphens in a row at this point.
663@item pixels
664This is the font height, in pixels.
665@item height
666This is the font height on the screen, measured in tenths of a printer's
667point---approximately 1/720 of an inch. In other words, it is the point
668size of the font, times ten. For a given vertical resolution,
669@var{height} and @var{pixels} are proportional; therefore, it is common
670to specify just one of them and use @samp{*} for the other.
671@item horiz
672This is the horizontal resolution, in pixels per inch, of the screen for
673which the font is intended.
674@item vert
675This is the vertical resolution, in pixels per inch, of the screen for
676which the font is intended. Normally the resolution of the fonts on
677your system is the right value for your screen; therefore, you normally
678specify @samp{*} for this and @var{horiz}.
679@item spacing
680This is @samp{m} (monospace), @samp{p} (proportional) or @samp{c}
681(character cell).
682@item width
683This is the average character width, in pixels, multiplied by ten.
684@item charset
685This is the character set that the font depicts.
686Normally you should use @samp{iso8859-1}.
687@end table
688
689@cindex listing system fonts
690 You will probably want to use a fixed-width default font---that is,
691a font in which all characters have the same width. Any font with
692@samp{m} or @samp{c} in the @var{spacing} field of the long name is a
693fixed-width font. Here's how to use the @code{xlsfonts} program to
694list all the fixed-width fonts available on your system:
695
696@example
697xlsfonts -fn '*x*' | egrep "^[0-9]+x[0-9]+"
698xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-m*'
699xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-c*'
700@end example
701
702@noindent
703To see what a particular font looks like, use the @code{xfd} command.
704For example:
705
706@example
707xfd -fn 6x13
708@end example
709
710@noindent
711displays the entire font @samp{6x13}.
712
713 While running Emacs, you can set the font of the current frame
714(@pxref{Frame Parameters}) or for a specific kind of text
715(@pxref{Faces}).
716
e15044ea 717@node Colors
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718@appendixsec Window Color Options
719@cindex color of window
720@cindex text colors, from command line
721
722@findex list-colors-display
723@cindex available colors
724 On a color display, you can specify which color to use for various
725parts of the Emacs display. To find out what colors are available on
726your system, type @kbd{M-x list-colors-display}, or press
727@kbd{C-Mouse-2} and select @samp{Display Colors} from the pop-up menu.
728If you do not specify colors, on windowed displays the default for the
729background is white and the default for all other colors is black. On a
730monochrome display, the foreground is black, the background is white,
731and the border is gray if the display supports that. On terminals, the
732background is usually black and the foreground is white.
733
734 Here is a list of the command-line options for specifying colors:
735
736@table @samp
737@item -fg @var{color}
738@opindex -fg
739@itemx --foreground-color=@var{color}
740@opindex --foreground-color
741@cindex foreground color, command-line argument
742Specify the foreground color. @var{color} should be a standard color
743name, or a numeric specification of the color's red, green, and blue
744components as in @samp{#4682B4} or @samp{RGB:46/82/B4}.
745@item -bg @var{color}
746@opindex -bg
747@itemx --background-color=@var{color}
748@opindex --background-color
749@cindex background color, command-line argument
750Specify the background color.
751@item -bd @var{color}
752@opindex -bd
753@itemx --border-color=@var{color}
754@opindex --border-color
755@cindex border color, command-line argument
756Specify the color of the border of the X window.
757@item -cr @var{color}
758@opindex -cr
759@itemx --cursor-color=@var{color}
760@opindex --cursor-color
761@cindex cursor color, command-line argument
762Specify the color of the Emacs cursor which indicates where point is.
763@item -ms @var{color}
764@opindex -ms
765@itemx --mouse-color=@var{color}
766@opindex --mouse-color
767@cindex mouse pointer color, command-line argument
768Specify the color for the mouse cursor when the mouse is in the Emacs window.
769@item -r
770@opindex -r
771@itemx -rv
772@opindex -rv
773@itemx --reverse-video
774@opindex --reverse-video
775@cindex reverse video, command-line argument
776Reverse video---swap the foreground and background colors.
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777@item --color=@var{mode}
778@opindex --color
779@cindex standard colors on a character terminal
780For a character terminal only, specify the mode of color support. The
781parameter @var{mode} can be one of the following:
782@table @samp
783@item never
784@itemx no
785Don't use colors even if the terminal's capabilities specify color
786support.
787@item default
788@itemx auto
789Same as when @option{--color} is not used at all: Emacs detects at
790startup whether the terminal supports colors, and if it does, turns on
791colored display.
792@item always
793@itemx yes
794@itemx ansi8
795Turn on the color support unconditionally, and use color commands
796specified by the ANSI escape sequences for the 8 standard colors.
797@item @var{num}
798Use color mode for @var{num} colors. If @var{num} is -1, turn off
799color support (equivalent to @samp{never}); if it is 0, use the
800default color support for this terminal (equivalent to @samp{auto});
801otherwise use an appropriate standard mode for @var{num} colors. If
802there is no mode that supports @var{num} colors, Emacs acts as if
803@var{num} were 0, i.e.@: it uses the terminal's default color support
804mode.
805@end table
806If @var{mode} is omitted, it defaults to @var{ansi8}.
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807@end table
808
809 For example, to use a coral mouse cursor and a slate blue text cursor,
810enter:
811
812@example
813emacs -ms coral -cr 'slate blue' &
814@end example
815
816 You can reverse the foreground and background colors through the
817@samp{-rv} option or with the X resource @samp{reverseVideo}.
818
819 The @samp{-fg}, @samp{-bg}, and @samp{-rv} options function on
820text-only terminals as well as on window systems.
821
822@node Window Size X
d7beb4c9 823@appendixsec Options for Window Size and Position
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824@cindex geometry of Emacs window
825@cindex position and size of Emacs frame
826@cindex width and height of Emacs frame
d7beb4c9 827@cindex specifying fullscreen for Emacs frame
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829 Here is a list of the command-line options for specifying size and
830position of the initial Emacs frame:
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831
832@table @samp
833@item -g @var{width}x@var{height}@r{[@{}+-@r{@}}@var{xoffset}@r{@{}+-@r{@}}@var{yoffset}@r{]]}
834@opindex -g
835Specify window size @var{width} and @var{height} (measured in character
836columns and lines), and positions @var{xoffset} and @var{yoffset}
837(measured in pixels).
838
839@item --geometry=@var{width}x@var{height}@r{[@{}+-@r{@}}@var{xoffset}@r{@{}+-@r{@}}@var{yoffset}@r{]]}
840@opindex --geometry
841This is another way of writing the same thing.
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842
843@item -fs
844@opindex -fs
845@itemx --fullscreen
846@opindex --fullscreen
847@cindex fullscreen, command-line argument
848Specify that width and height shall be the size of the screen.
849
850@item -fh
851@opindex -fh
852@itemx --fullheight
853@opindex --fullheight
854@cindex fullheight, command-line argument
855Specify that the height shall be the height of the screen.
856
857@item -fw
858@opindex -fw
859@itemx --fullwidth
860@opindex --fullwidth
861@cindex fullwidth, command-line argument
862Specify that the width shall be the width of the screen.
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863@end table
864
d7beb4c9 865
e428626a 866@noindent
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867In the @samp{--geometry} option, @code{@r{@{}+-@r{@}}} means either a plus
868 sign or a minus sign. A plus
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869sign before @var{xoffset} means it is the distance from the left side of
870the screen; a minus sign means it counts from the right side. A plus
871sign before @var{yoffset} means it is the distance from the top of the
872screen, and a minus sign there indicates the distance from the bottom.
873The values @var{xoffset} and @var{yoffset} may themselves be positive or
874negative, but that doesn't change their meaning, only their direction.
875
876 Emacs uses the same units as @code{xterm} does to interpret the geometry.
877The @var{width} and @var{height} are measured in characters, so a large font
878creates a larger frame than a small font. (If you specify a proportional
879font, Emacs uses its maximum bounds width as the width unit.) The
880@var{xoffset} and @var{yoffset} are measured in pixels.
881
882 Since the mode line and the echo area occupy the last 2 lines of the
883frame, the height of the initial text window is 2 less than the height
884specified in your geometry. In non-X-toolkit versions of Emacs, the
885menu bar also takes one line of the specified number. But in the X
886toolkit version, the menu bar is additional and does not count against
887the specified height. The tool bar, if present, is also additional.
888
889 You do not have to specify all of the fields in the geometry
890specification.
891
892 If you omit both @var{xoffset} and @var{yoffset}, the window manager
893decides where to put the Emacs frame, possibly by letting you place
894it with the mouse. For example, @samp{164x55} specifies a window 164
895columns wide, enough for two ordinary width windows side by side, and 55
896lines tall.
897
898 The default width for Emacs is 80 characters and the default height is
89940 lines. You can omit either the width or the height or both. If
900you start the geometry with an integer, Emacs interprets it as the
901width. If you start with an @samp{x} followed by an integer, Emacs
902interprets it as the height. Thus, @samp{81} specifies just the width;
903@samp{x45} specifies just the height.
904
905 If you start with @samp{+} or @samp{-}, that introduces an offset,
906which means both sizes are omitted. Thus, @samp{-3} specifies the
907@var{xoffset} only. (If you give just one offset, it is always
908@var{xoffset}.) @samp{+3-3} specifies both the @var{xoffset} and the
909@var{yoffset}, placing the frame near the bottom left of the screen.
910
911 You can specify a default for any or all of the fields in
912@file{.Xdefaults} file, and then override selected fields with a
913@samp{--geometry} option.
914
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915
916 When using one of @samp{--fullscreen}, @samp{--fullwidth} or
917@samp{--fullheight} there may be some space around the frame
918anyway. That is because Emacs rounds the sizes so they are an
919even number of character heights and widths.
920
921 Some window managers have options that can make them ignore both
922program-specified and user-specified positions (sawfish is one).
923If these are set, Emacs fails to position the window correctly.
924
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925@node Borders X
926@appendixsec Internal and External Borders
927@cindex borders (X Window System)
928
929 An Emacs frame has an internal border and an external border. The
930internal border is an extra strip of the background color around the
931text portion of the frame. Emacs itself draws the internal border.
932The external border is added by the window manager outside the frame;
933depending on the window manager you use, it may contain various boxes
934you can click on to move or iconify the window.
935
936@table @samp
937@item -ib @var{width}
938@opindex -ib
939@itemx --internal-border=@var{width}
940@opindex --internal-border
941@cindex border width, command-line argument
942Specify @var{width} as the width of the internal border, in pixels.
943
944@item -bw @var{width}
945@opindex -bw
946@itemx --border-width=@var{width}
947@opindex --border-width
948Specify @var{width} as the width of the main border, in pixels.
949@end table
950
951 When you specify the size of the frame, that does not count the
952borders. The frame's position is measured from the outside edge of the
953external border.
954
955 Use the @samp{-ib @var{n}} option to specify an internal border
956@var{n} pixels wide. The default is 1. Use @samp{-bw @var{n}} to
957specify the width of the external border (though the window manager may
958not pay attention to what you specify). The default width of the
959external border is 2.
960
961@node Title X
962@appendixsec Frame Titles
963
964 An Emacs frame may or may not have a specified title. The frame
965title, if specified, appears in window decorations and icons as the
966name of the frame. If an Emacs frame has no specified title, the
967default title has the form @samp{@var{invocation-name}@@@var{machine}}
968(if there is only one frame) or the selected window's buffer name (if
969there is more than one frame).
970
971 You can specify a title for the initial Emacs frame with a command
972line option:
973
974@table @samp
975@item -title @var{title}
976@opindex --title
977@itemx --title=@var{title}
978@itemx -T @var{title}
979@opindex -T
980@cindex frame title, command-line argument
981Specify @var{title} as the title for the initial Emacs frame.
982@end table
983
186e9bcc 984 The @samp{--name} option (@pxref{Resources}) also specifies the title
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985for the initial Emacs frame.
986
987@node Icons X
988@appendixsec Icons
989@cindex icons (X Window System)
990
991 Most window managers allow the user to ``iconify'' a frame, removing
992it from sight, and leaving a small, distinctive ``icon'' window in its
993place. Clicking on the icon window makes the frame itself appear again.
994If you have many clients running at once, you can avoid cluttering up
995the screen by iconifying most of the clients.
996
997@table @samp
998@item -i
999@opindex -i
1000@itemx --icon-type
1001@opindex --icon-type
1002@cindex Emacs icon, a gnu
1003Use a picture of a gnu as the Emacs icon.
1004
1005@item -iconic
1006@opindex --iconic
1007@itemx --iconic
1008@cindex start iconified, command-line argument
1009Start Emacs in iconified state.
1010@end table
1011
1012 The @samp{-i} or @samp{--icon-type} option tells Emacs to use an icon
1013window containing a picture of the GNU gnu. If omitted, Emacs lets the
1014window manager choose what sort of icon to use---usually just a small
1015rectangle containing the frame's title.
1016
1017 The @samp{-iconic} option tells Emacs to begin running as an icon,
1018rather than showing a frame right away. In this situation, the icon
1019is the only indication that Emacs has started; the text frame doesn't
1020appear until you deiconify it.