@c This is part of the Emacs manual.
@c Copyright (C) 1985, 1986, 1987, 1993 Free Software Foundation, Inc.
@c See file emacs.texi for copying conditions.
@node Command Arguments, Antinews, Service, Top
@appendix Command Line Options and Arguments
@cindex command line arguments
@cindex arguments (from shell)

  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 that are not options specify files to visit.  Emacs visits
the specified files while it starts up.  (The last file name on your
command line is the one you see displayed, but the rest are all there in
other buffers.)

  You can use options to specify other things, such as the size and
position of the Emacs window if you are running it under the X Window
System.  A few arguments support advanced usage, like running Lisp
functions on files in batch mode.

  There are two kinds of options: @dfn{ordinary options} and
@dfn{initial options}.  Ordinary options can appear in any order and can
be intermixed with file names to visit.  These and file names are called
@dfn{ordinary arguments}.  Emacs processes all of these in the order
they are written.  Initial options must come at the beginning of the
command line.

@menu
* Ordinary Arguments::	Arguments to visit files, load libraries,
			  and call functions.
* Initial Options::     Arguments that must come at the start of the command.
* Command Example::     Examples of using command line arguments.
* Resume Arguments::	Specifying arguments when you resume a running Emacs.

* Display X::           Changing the default display and using remote login.
* Font X::	        Choosing a font for text, under X.
* Colors X::	        Choosing colors, under X.
* Window Size X::       Start-up window size, under X.
* Borders X::	        Internal and external borders, under X.
* Icons X::             Choosing what sort of icon to use, under X.
* Resources X::         Advanced use of classes and resources, under X.
@end menu

@node Ordinary Arguments
@appendixsec Ordinary Arguments

  Here is a table of the ordinary arguments and options:

@table @samp
@item @var{file}
Visit @var{file} using @code{find-file}.  @xref{Visiting}.

@item +@var{linenum} @var{file}
Visit @var{file} using @code{find-file}, then go to line number
@var{linenum} in it.

@item -l @var{file}
@itemx -load @var{file}
Load a file @var{file} of Lisp code with the function @code{load}.
@xref{Lisp Libraries}.

@item -f @var{function}
@itemx -funcall @var{function}
Call Lisp function @var{function} with no arguments.

@item -insert @var{file}
Insert the contents of @var{file} into the current buffer.
This is like what @kbd{M-x insert-buffer} does; @xref{Misc File Ops}.

@item -kill
Exit from Emacs without asking for confirmation.
@end table

@node Initial Options
@appendixsec Initial Options

  The initial options are recognized only at the beginning of the
command line.  If you use more than one of them, they must appear in the
order that they appear in this table.

@table @samp
@item -t @var{device}
Use @var{device} as the device for terminal input and output.

@item -d @var{display}
When running with the X window system, use the display named @var{display}
to make the window that serves as Emacs's terminal.

@cindex batch mode
@item -batch
Run Emacs in @dfn{batch mode}, which means that the text being edited is
not displayed and the standard Unix interrupt characters such as @kbd{C-z}
and @kbd{C-c} continue to have their normal effect.  Emacs in batch mode
outputs to @code{stdout} only what would normally be printed in the echo
area under program control.

Batch mode is used for running programs written in Emacs Lisp from
shell scripts, makefiles, and so on.  Normally the @samp{-l} option
or @samp{-f} option will be used as well, to invoke a Lisp program
to do the batch processing.

@samp{-batch} implies @samp{-q} (do not load an init file).  It also causes
Emacs to kill itself after all command options have been processed.  In
addition, auto-saving is not done except in buffers for which it has been
explicitly requested.

@item -q
@itemx -no-init-file
Do not load your Emacs init file @file{~/.emacs}.

@item -u @var{user}
@itemx -user @var{user}
Load @var{user}'s Emacs init file @file{~@var{user}/.emacs} instead of
your own.
@end table

@vindex command-line-args
  The init file can get access to the values of the command line arguments as
the elements of a list in the variable @code{command-line-args}.  (The list
contains only the arguments from the first table above.  Emacs processes the
arguments from the second table before building the list.)  The init file can
override the normal processing of the other arguments by setting this
variable.

@node Command Example
@appendixsec Command Argument Example

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

@example
emacs -batch foo.c -l hack-c -f save-buffer -kill > log
@end example

@noindent
This says to visit @file{foo.c}, load @file{hack-c.el} (which makes
changes in the visited file), save @file{foo.c} (note that
@code{save-buffer} is the function that @kbd{C-x C-s} is bound to), and
then exit to the shell that this command was done with.  The initial
option @samp{-batch} guarantees there will be no problem redirecting
output to @file{log}, because Emacs will not assume that it has a
display terminal to work with.

@node Resume Arguments
@appendixsec Resuming Emacs with Arguments

  You can specify ordinary arguments for Emacs when you resume it after
a suspension.  To prepare for this, put the following code in your
@file{.emacs} file (@pxref{Hooks}):

@example
(add-hook 'suspend-hook 'resume-suspend-hook)
@end example

  As further preparation, you must execute the shell script
@file{emacs.csh} (if you use CSH as your shell) or @file{emacs.bash} (if
you use BASH as your shell).  These scripts define an alias named
@code{edit}, which will resume Emacs give it new command line arguments
such as files to visit.

  Only ordinary 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
@code{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; no way to define a command that could be
made the value of @code{EDITOR}, for example.  Therefore, this feature
does not take the place of the the Emacs Server feature.  @xref{Emacs
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
@file{/tmp/.esrv@dots{}} still exists.  If this happens, find that
file and delete it.

@node Display X
@appendixsec Specifying the Display Name 
@cindex display name (X Windows)
@cindex @code{DISPLAY} environment variable

  The environment variable @code{DISPLAY} tells all X clients where to
display their windows.  Its value is set up 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 use login
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 @code{DISPLAY} environment variable is:

@smallexample
@var{host}:@var{display}.@var{screen}
@end smallexample

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

  If your host is named @samp{glasperle} and your server is the first
(or perhaps the only) server listed in the configuration, your
@code{DISPLAY} is @samp{glasperle:0.0}.

  You can specify the display name explicitly when you run Emacs, either
by changing the @code{DISPLAY} variable, or with the option @samp{-d
@var{display}} or @samp{-display @var{display}}.  These are initial
options; they must come at the beginning of the command line.
@xref{Initial Options}.  Here is an example:

@smallexample
emacs -display glasperle:0 &
@end smallexample

  You can inhibit the direct use of X with the @samp{-nw} option.  This
is also an initial option.  This option tells Emacs to display using
ordinary ASCII on its controlling terminal.

  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:

@smallexample
Xlib:  connection to "glasperle:0.0" refused by server
@end smallexample

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

@node Font X
@appendixsec Font Specification Options
@cindex font name (X Windows)

@c ??? Check font name
  By default, Emacs displays text in the font named @samp{9x15}, which
makes each character nine pixels wide and fifteen pixels high.  You can
specify a different font on your command line through the option
@samp{-fn @var{name}}.  The @samp{-font} option is a synonym for
@samp{-fn}.

  Here is how to specify the font @samp{6x13}:

@example
emacs -fn 6x13 &
@end example

@noindent
You can also do this in your @file{.Xdefaults} file:

@example
emacs.font:      6x13
@end example

  Use only fixed width fonts---that is, fonts in which all characters
have the same width.  Emacs cannot yet handle display properly for
variable width fonts.  Fixed width fonts include the one named
@samp{fixed}, and fonts with names in the form @var{n}x@var{n}, such as
@samp{6x13}, @samp{8x13}, and @samp{9x15}.  Under the font-naming
conventions in X11 Release 4 or later, any font with @samp{m} or
@samp{c} in the eleventh field of the name is a fixed width font.

  Here's how to use the @code{xlsfonts} program to list all the fixed
width fonts available on your system:

@example
xlsfonts -fn '*x*'
xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-m*'
xlsfonts -fn '*-*-*-*-*-*-*-*-*-*-*-c*'
@end example

@noindent
To see what a particular font looks like, use the @code{xfd} command.
For example:

@example
xfd -fn 6x13
@end example

@noindent
displays the entire font @samp{6x13}.

  While running Emacs, you can set the font of the current frame
(@pxref{Frame Parameters}) or for a specific kind of text
(@pxref{Faces}).

@node Colors X
@appendixsec Window Color Options
@cindex color of window (X Windows)

  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, look at the @file{/usr/lib/X11/rgb.txt} file.  If you do
not specify colors, the default for the background is white and the
default for all other colors is black.

  On a monochrome (black and white) display, the foreground is black, the
background is white, and the border is grey.  You can reverse the foreground
and background colors through the @samp{-r} option or the @samp{reverseVideo}
resource.

  Here is a list of the options for specifying colors:

@table @samp
@item -fg @var{color} 
Specify the foreground color.
@item -bg @var{color} 
Specify the background color.
@item -bd @var{color} 
Specify the color of the border of the X window.
@item -cr @var{color} 
Specify the color of the Emacs cursor which indicates where point is.
@item -ms @var{color} 
Specify the color for the mouse cursor when the mouse is in the Emacs window.
@end table

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

@example
emacs -ms coral -cr 'slate blue' &
@end example

@node Window Size X
@appendixsec Options for Window Geometry
@cindex geometry (X Windows)

  The @samp{-geometry} option controls the size and position of the
initial Emacs frame.  Here is the format for specifying the window
geometry:

@smallexample
@var{width}x@var{height}@{+-@}@var{xoffset}@{+-@}@var{yoffset}
@end smallexample

@noindent
where @var{width} specifies the number of characters displayed on a
line, @var{height} specifies the number of lines displayed, a positive
@var{xoffset} specifies the distance from the left side of the screen, a
negative @var{xoffset} specifies the distance from the right side of the
screen, a positive @var{yoffset} specifies the distance from the top of
the screen, and a negative @var{yoffset} specifies the distance from the
bottom of the screen.

  Emacs uses the same units as @code{xterm} does to interpret the geometry.
The @var{width} and @var{height} are measured in characters, so a large font
creates a larger frame than a small font.  The @var{xoffset} and
@var{yoffset} are measured in pixels.

  Since the 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.

  You do not have to specify all of the fields in the geometry
specification.  The default width for Emacs is 80 characters and the
default height is 24 characters.  You can omit either the width or the
height or both.

  If you omit both @var{xoffset} nor @var{yoffset}, the window manager
decides where to put the Emacs frame, possibly by letting you place
it with the mouse.  For example, @samp{164x55} specifies a window 164
columns wide, enough for two ordinary width windows side by side, and 55
lines tall.

  If you start the geometry with an integer, Emacs interprets it as the
width.  If you start with an @samp{x} followed by an integer, Emacs
interprets it as the height.  Thus, @samp{81} specifies just the width;
@samp{x45} specifies just the height.

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

  You can specify a default for any or all of the fields in
@file{.Xdefaults} file, and then override selected fields through a
@samp{-geometry} option.

@node Borders X
@appendixsec Internal and External Borders
@cindex borders (X Windows)

  An Emacs frame has an internal border and an external border.  The
internal border is an extra strip of the background color around all
four edges of the frame.  Emacs itself adds the internal border.  The
external border is added by the window manager outside the internal
border; it may contain various boxes you can click on to move or iconify
the window.

  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 @samp{-ib @var{n}} option to specify an internal border
@var{n} pixels wide.  The default is 1.  Use @samp{-b @var{n}} to
specify the width of the external border (though the window manager may
add to this on certain edges).  The default width of the external border
is 2.

@node Icons X
@appendixsec Icons
@cindex icons (X Windows)

  Most window managers allow the user to ``iconify'' a frame, removing
it from sight, and leaving a small, distinctive ``icon'' window in its
place.  Clicking on the icon window will make the original frame visible
again.  If a user has many clients running at once, they can avoid
cluttering up their screen by iconifying all but the clients currently
in use.

  The @samp{-i} and @samp{-itype} option tells Emacs to use an icon
window containing a picture of the GNU gnu.  If omitted, Emacs lets the
window manager choose what sort of icon to use --- usually just a small
rectangle containing the frame's title.

  The @samp{-iconic} option tells Emacs to begin running as an icon,
rather than opening a frame right away.  In this situation, the icon
window provides only indication that Emacs has started; the usual text
frame doesn't appear until you de-iconify it.

@node Resources X
@appendixsec X Resources

  Programs running under the X Window System organize their user options
under a hierarchy of classes and resources.  You can specify default
values for these options in your X resources file, usually named
@file{~/.Xdefaults}.

  Each line in the file specifies a value for one option or for a
collection of related options, for one program or for several programs
(perhaps even all programs).

  Programs define named resources with particular meanings.  They also
define how to group resources into named classes.  For instance, in
Emacs, the @samp{internalBorder} resource controls the width of the
internal border, and the @samp{borderWidth} resource controls the width
of the external border.  Both of these resources are part of the
@samp{BorderWidth} class.  Case distinctions are significant in these
names.

  In @file{~/.Xdefaults}, you can specify a value for a single resource
on one line, like this:

@example
emacs.borderWidth: 2
@end example

@noindent
Or you can use a class name to specify the same value for all resources
in that class.  Here's an example:

@example
emacs.BorderWidth: 2
@end example

  If you specify a value for a class, it becomes the default for all
resources in that class.  You can specify values for individual
resources as well; these override the class value, for those particular
resources.  Thus, this example specifies 2 as the default width for all
borders, but overrides this value with 4 for the external border:

@example
emacs.Borderwidth: 2
emacs.borderwidth: 4
@end example

  The order in which the lines appear in the file does not matter.
Also, command-line options always override the X resources file.

  The string @samp{emacs} in the examples above is also a resource
name.  It actually represents the name of the executable file that you
invoke to run Emacs.  If Emacs is installed under a different name, it
look for resources under that name instead of @samp{emacs}.

  You can tell Emacs to use a different name instead of the name of the
executable file, with the option @samp{-rn @var{name}}.  Then that Emacs
job uses @var{name} instead of @samp{Emacs} to look up all of its option
values in the X resource file.

  The resources that name Emacs invocations also belong to a class; its
name is @samp{Emacs}.  To specify options for all Emacs jobs, no matter
what name is used to run them, write @samp{Emacs} instead of
@samp{emacs}, like this:

@example
Emacs.BorderWidth: 2
Emacs.borderWidth: 4
@end example

  The following table lists the resource names that designate options
for Emacs, each with the class that it belongs to:

@table @asis
@item @code{background} (class @code{Background})
Background color name.

@item @code{bitmapIcon} (class @code{BitMapIcon})
Use kitchen sink icon if @samp{on}, let the window manager choose an icon if
@samp{off}.

@item @code{borderColor} (class @code{BorderColor})
Color name for external border.

@item @code{borderWidth} (class @code{BorderWidth})
Width in pixels of external border.

@item @code{cursorColor} (class @code{Foreground})
Color name for text cursor (point).

@item @code{font} (class @code{Font})
Font name for text.

@item @code{foreground} (class @code{Foreground})
Color name for text.

@item @code{geometry} (class @code{Geometry})
Window size and position.

@item @code{iconName} (class @code{Title})
Name to display in icon.

@item @code{internalBorder} (class @code{BorderWidth})
Width in pixels of internal border.

@item @code{paneFont} (class @code{Font})
Font name for menu pane titles.

@item @code{pointerColor} (class @code{Foreground})
Color of mouse cursor.

@item @code{reverseVideo} (class @code{ReverseVideo})
Switch foreground and background default colors if @samp{on}, use colors as
specified if @samp{off}.

@item @code{selectionFont} (class @code{Font})
Font name for menu items.

@item @code{title} (class @code{Title})
Name to display in title bar of initial Emacs frame.
@end table
