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/* Fully extensible Emacs, running on Unix, intended for GNU.
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Copyright (C) 1985-1987, 1993-1995, 1997-1999, 2001-2016 Free Software
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Foundation, Inc.
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This file is part of GNU Emacs.

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GNU Emacs is free software: you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation, either version 3 of the License, or (at
your option) any later version.
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GNU Emacs is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

You should have received a copy of the GNU General Public License
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along with GNU Emacs.  If not, see <http://www.gnu.org/licenses/>.  */
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#define INLINE EXTERN_INLINE
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#include <config.h>
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#include <errno.h>
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#include <fcntl.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <sys/types.h>
#include <sys/file.h>
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#include <unistd.h>

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#include <close-stream.h>
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#define MAIN_PROGRAM
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#include "lisp.h"

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#ifdef WINDOWSNT
#include <fcntl.h>
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#include <sys/socket.h>
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#include <mbstring.h>
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#include "w32.h"
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#include "w32heap.h"
#endif

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#if defined WINDOWSNT || defined HAVE_NTGUI
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#include "w32select.h"
#include "w32font.h"
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#include "w32common.h"
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#endif

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#if defined CYGWIN
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#include "cygw32.h"
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#endif

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#ifdef MSDOS
#include <binary-io.h>
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#include "dosfns.h"
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#endif

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#ifdef HAVE_LIBSYSTEMD
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# include <systemd/sd-daemon.h>
# include <sys/socket.h>
#endif
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#ifdef HAVE_WINDOW_SYSTEM
#include TERM_HEADER
#endif /* HAVE_WINDOW_SYSTEM */

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#include "intervals.h"
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#include "character.h"
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#include "buffer.h"
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#include "window.h"
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#include "xwidget.h"
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#include "atimer.h"
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#include "blockinput.h"
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#include "syssignal.h"
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#include "process.h"
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#include "frame.h"
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#include "termhooks.h"
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#include "keyboard.h"
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#include "keymap.h"
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#include "category.h"
#include "charset.h"
#include "composite.h"
#include "dispextern.h"
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#include "regex.h"
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#include "sheap.h"
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#include "syntax.h"
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#include "sysselect.h"
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#include "systime.h"
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#include "puresize.h"
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#include "getpagesize.h"
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#include "gnutls.h"

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#if (defined PROFILING \
     && (defined __FreeBSD__ || defined GNU_LINUX || defined __MINGW32__))
# include <sys/gmon.h>
extern void moncontrol (int mode);
#endif

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#ifdef HAVE_SETLOCALE
#include <locale.h>
#endif

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#if HAVE_WCHAR_H
# include <wchar.h>
#endif

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#ifdef HAVE_SETRLIMIT
#include <sys/time.h>
#include <sys/resource.h>
#endif

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static const char emacs_version[] = PACKAGE_VERSION;
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static const char emacs_copyright[] = COPYRIGHT;
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static const char emacs_bugreport[] = PACKAGE_BUGREPORT;
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/* Empty lisp strings.  To avoid having to build any others.  */
Lisp_Object empty_unibyte_string, empty_multibyte_string;
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#ifdef WINDOWSNT
/* Cache for externally loaded libraries.  */
Lisp_Object Vlibrary_cache;
#endif

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/* Set after Emacs has started up the first time.
   Prevents reinitialization of the Lisp world and keymaps
   on subsequent starts.  */
bool initialized;
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/* Set to true if this instance of Emacs might dump.  */
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#ifndef DOUG_LEA_MALLOC
static
#endif
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bool might_dump;

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#ifdef DARWIN_OS
extern void unexec_init_emacs_zone (void);
#endif

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/* If true, Emacs should not attempt to use a window-specific code,
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   but instead should use the virtual terminal under which it was started.  */
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bool inhibit_window_system;
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/* If true, a filter or a sentinel is running.  Tested to save the match
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   data on the first attempt to change it inside asynchronous code.  */
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bool running_asynch_code;
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#if defined (HAVE_X_WINDOWS) || defined (HAVE_NS)
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/* If true, -d was specified, meaning we're using some window system.  */
bool display_arg;
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#endif

/* An address near the bottom of the stack.
   Tells GC how to save a copy of the stack.  */
char *stack_bottom;

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#ifdef GNU_LINUX
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/* The gap between BSS end and heap start as far as we can tell.  */
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static uprintmax_t heap_bss_diff;
#endif
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/* To run as a background daemon under Cocoa or Windows,
   we must do a fork+exec, not a simple fork.
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   On Cocoa, CoreFoundation lib fails in forked process:
   http://developer.apple.com/ReleaseNotes/
   CoreFoundation/CoreFoundation.html)

   On Windows, a Cygwin fork child cannot access the USER subsystem.

   We mark being in the exec'd process by a daemon name argument of
   form "--daemon=\nFD0,FD1\nNAME" where FD are the pipe file descriptors,
   NAME is the original daemon name, if any. */
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#if defined NS_IMPL_COCOA || (defined HAVE_NTGUI && defined CYGWIN)
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# define DAEMON_MUST_EXEC
#endif

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/* True means running Emacs without interactive terminal.  */
bool noninteractive;
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/* True means remove site-lisp directories from load-path.  */
bool no_site_lisp;
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/* True means put details like time stamps into builds.  */
bool build_details;

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/* Name for the server started by the daemon.*/
static char *daemon_name;
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/* 0 not a daemon, 1 new-style (foreground), 2 old-style (background).  */
int daemon_type;

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#ifndef WINDOWSNT
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/* Pipe used to send exit notification to the background daemon parent at
   startup.  On Windows, we use a kernel event instead.  */
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int daemon_pipe[2];
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#else
HANDLE w32_daemon_event;
#endif
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/* Save argv and argc.  */
char **initial_argv;
int initial_argc;
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static void sort_args (int argc, char **argv);
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static void syms_of_emacs (void);
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/* C99 needs each string to be at most 4095 characters, and the usage
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   strings below are split to not overflow this limit.  */
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static char const *const usage_message[] =
  { "\
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\n\
Run Emacs, the extensible, customizable, self-documenting real-time\n\
display editor.  The recommended way to start Emacs for normal editing\n\
is with no options at all.\n\
\n\
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Run M-x info RET m emacs RET m emacs invocation RET inside Emacs to\n\
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read the main documentation for these command-line arguments.\n\
\n\
Initialization options:\n\
\n\
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",
    "\
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--batch                     do not do interactive display; implies -q\n\
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--chdir DIR                 change to directory DIR\n\
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--daemon, --old-daemon[=NAME] start a (named) server in the background\n\
--new-daemon[=NAME]         start a (named) server in the foreground\n\
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--debug-init                enable Emacs Lisp debugger for init file\n\
--display, -d DISPLAY       use X server DISPLAY\n\
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",
    "\
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--no-build-details          do not add build details such as time stamps\n\
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--no-desktop                do not load a saved desktop\n\
--no-init-file, -q          load neither ~/.emacs nor default.el\n\
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--no-loadup, -nl            do not load loadup.el into bare Emacs\n\
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--no-site-file              do not load site-start.el\n\
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--no-x-resources            do not load X resources\n\
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--no-site-lisp, -nsl        do not add site-lisp directories to load-path\n\
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--no-splash                 do not display a splash screen on startup\n\
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--no-window-system, -nw     do not communicate with X, ignoring $DISPLAY\n\
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",
    "\
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--quick, -Q                 equivalent to:\n\
                              -q --no-site-file --no-site-lisp --no-splash\n\
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                              --no-x-resources\n\
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--script FILE               run FILE as an Emacs Lisp script\n\
--terminal, -t DEVICE       use DEVICE for terminal I/O\n\
--user, -u USER             load ~USER/.emacs instead of your own\n\
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\n\
",
    "\
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Action options:\n\
\n\
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FILE                    visit FILE using find-file\n\
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+LINE                   go to line LINE in next FILE\n\
+LINE:COLUMN            go to line LINE, column COLUMN, in next FILE\n\
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--directory, -L DIR     prepend DIR to load-path (with :DIR, append DIR)\n\
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--eval EXPR             evaluate Emacs Lisp expression EXPR\n\
--execute EXPR          evaluate Emacs Lisp expression EXPR\n\
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",
    "\
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--file FILE             visit FILE using find-file\n\
--find-file FILE        visit FILE using find-file\n\
--funcall, -f FUNC      call Emacs Lisp function FUNC with no arguments\n\
--insert FILE           insert contents of FILE into current buffer\n\
--kill                  exit without asking for confirmation\n\
--load, -l FILE         load Emacs Lisp FILE using the load function\n\
--visit FILE            visit FILE using find-file\n\
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\n\
",
    "\
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Display options:\n\
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\n\
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--background-color, -bg COLOR   window background color\n\
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--basic-display, -D             disable many display features;\n\
                                  used for debugging Emacs\n\
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--border-color, -bd COLOR       main border color\n\
--border-width, -bw WIDTH       width of main border\n\
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",
    "\
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--color, --color=MODE           override color mode for character terminals;\n\
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                                  MODE defaults to `auto', and\n\
                                  can also be `never', `always',\n\
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                                  or a mode name like `ansi8'\n\
--cursor-color, -cr COLOR       color of the Emacs cursor indicating point\n\
--font, -fn FONT                default font; must be fixed-width\n\
--foreground-color, -fg COLOR   window foreground color\n\
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",
    "\
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--fullheight, -fh               make the first frame high as the screen\n\
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--fullscreen, -fs               make the first frame fullscreen\n\
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--fullwidth, -fw                make the first frame wide as the screen\n\
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--maximized, -mm                make the first frame maximized\n\
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--geometry, -g GEOMETRY         window geometry\n\
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",
    "\
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--no-bitmap-icon, -nbi          do not use picture of gnu for Emacs icon\n\
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--iconic                        start Emacs in iconified state\n\
--internal-border, -ib WIDTH    width between text and main border\n\
--line-spacing, -lsp PIXELS     additional space to put between lines\n\
--mouse-color, -ms COLOR        mouse cursor color in Emacs window\n\
--name NAME                     title for initial Emacs frame\n\
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",
    "\
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--no-blinking-cursor, -nbc      disable blinking cursor\n\
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--reverse-video, -r, -rv        switch foreground and background\n\
--title, -T TITLE               title for initial Emacs frame\n\
--vertical-scroll-bars, -vb     enable vertical scroll bars\n\
--xrm XRESOURCES                set additional X resources\n\
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--parent-id XID                 set parent window\n\
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--help                          display this help and exit\n\
--version                       output version information and exit\n\
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\n\
",
    "\
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You can generally also specify long option names with a single -; for\n\
example, -batch as well as --batch.  You can use any unambiguous\n\
abbreviation for a --option.\n\
\n\
Various environment variables and window system resources also affect\n\
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the operation of Emacs.  See the main documentation.\n\
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\n\
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Report bugs to " PACKAGE_BUGREPORT ".  First, please see the Bugs\n\
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section of the Emacs manual or the file BUGS.\n"
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  };
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/* True if handling a fatal error already.  */
bool fatal_error_in_progress;
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#ifdef HAVE_NS
/* NS autrelease pool, for memory management.  */
static void *ns_pool;
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#endif

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#if !HAVE_SETLOCALE
static char *
setlocale (int cat, char const *locale)
{
  return 0;
}
#endif
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/* True if the current system locale uses UTF-8 encoding.  */
static bool
using_utf8 (void)
{
#ifdef HAVE_WCHAR_H
  wchar_t wc;
  mbstate_t mbs = { 0 };
  return mbrtowc (&wc, "\xc4\x80", 2, &mbs) == 2 && wc == 0x100;
#else
  return false;
#endif
}

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/* Report a fatal error due to signal SIG, output a backtrace of at
   most BACKTRACE_LIMIT lines, and exit.  */
_Noreturn void
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terminate_due_to_signal (int sig, int backtrace_limit)
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{
  signal (sig, SIG_DFL);
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  if (attempt_orderly_shutdown_on_fatal_signal)
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    {
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      /* If fatal error occurs in code below, avoid infinite recursion.  */
      if (! fatal_error_in_progress)
        {
          fatal_error_in_progress = 1;

          totally_unblock_input ();
          if (sig == SIGTERM || sig == SIGHUP || sig == SIGINT)
            Fkill_emacs (make_number (sig));

          shut_down_emacs (sig, Qnil);
          emacs_backtrace (backtrace_limit);
        }
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    }
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  /* Signal the same code; this time it will really be fatal.
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     Since we're in a signal handler, the signal is blocked, so we
     have to unblock it if we want to really receive it.  */
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#ifndef MSDOS
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  {
    sigset_t unblocked;
    sigemptyset (&unblocked);
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    sigaddset (&unblocked, sig);
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    pthread_sigmask (SIG_UNBLOCK, &unblocked, 0);
  }
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#endif
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  emacs_raise (sig);
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  /* This shouldn't be executed, but it prevents a warning.  */
  exit (1);
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}

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/* Code for dealing with Lisp access to the Unix command line.  */
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static void
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init_cmdargs (int argc, char **argv, int skip_args, char *original_pwd)
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{
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  int i;
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  Lisp_Object name, dir, handler;
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  ptrdiff_t count = SPECPDL_INDEX ();
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  Lisp_Object raw_name;
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  AUTO_STRING (slash_colon, "/:");
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  initial_argv = argv;
  initial_argc = argc;

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#ifdef WINDOWSNT
  /* Must use argv[0] converted to UTF-8, as it begets many standard
     file and directory names.  */
  {
    char argv0[MAX_UTF8_PATH];

    if (filename_from_ansi (argv[0], argv0) == 0)
      raw_name = build_unibyte_string (argv0);
    else
      raw_name = build_unibyte_string (argv[0]);
  }
#else
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  raw_name = build_unibyte_string (argv[0]);
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#endif
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  /* Add /: to the front of the name
     if it would otherwise be treated as magic.  */
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  handler = Ffind_file_name_handler (raw_name, Qt);
  if (! NILP (handler))
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    raw_name = concat2 (slash_colon, raw_name);
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  Vinvocation_name = Ffile_name_nondirectory (raw_name);
  Vinvocation_directory = Ffile_name_directory (raw_name);

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  /* If we got no directory in argv[0], search PATH to find where
     Emacs actually came from.  */
  if (NILP (Vinvocation_directory))
    {
      Lisp_Object found;
      int yes = openp (Vexec_path, Vinvocation_name,
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		       Vexec_suffixes, &found, make_number (X_OK), false);
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      if (yes == 1)
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	{
	  /* Add /: to the front of the name
	     if it would otherwise be treated as magic.  */
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	  handler = Ffind_file_name_handler (found, Qt);
	  if (! NILP (handler))
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	    found = concat2 (slash_colon, found);
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	  Vinvocation_directory = Ffile_name_directory (found);
	}
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    }
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  if (!NILP (Vinvocation_directory)
      && NILP (Ffile_name_absolute_p (Vinvocation_directory)))
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    /* Emacs was started with relative path, like ./emacs.
       Make it absolute.  */
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    {
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      Lisp_Object odir =
	original_pwd ? build_unibyte_string (original_pwd) : Qnil;

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      Vinvocation_directory = Fexpand_file_name (Vinvocation_directory, odir);
    }
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  Vinstallation_directory = Qnil;

  if (!NILP (Vinvocation_directory))
    {
      dir = Vinvocation_directory;
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#ifdef WINDOWSNT
      /* If we are running from the build directory, set DIR to the
	 src subdirectory of the Emacs tree, like on Posix
	 platforms.  */
      if (SBYTES (dir) > sizeof ("/i386/") - 1
	  && 0 == strcmp (SSDATA (dir) + SBYTES (dir) - sizeof ("/i386/") + 1,
			  "/i386/"))
	dir = Fexpand_file_name (build_string ("../.."), dir);
#else  /* !WINDOWSNT */
#endif
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      name = Fexpand_file_name (Vinvocation_name, dir);
      while (1)
	{
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	  Lisp_Object tem, lib_src_exists;
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	  Lisp_Object etc_exists, info_exists;

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	  /* See if dir contains subdirs for use by Emacs.
	     Check for the ones that would exist in a build directory,
	     not including lisp and info.  */
	  tem = Fexpand_file_name (build_string ("lib-src"), dir);
	  lib_src_exists = Ffile_exists_p (tem);
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#ifdef MSDOS
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	  /* MSDOS installations frequently remove lib-src, but we still
	     must set installation-directory, or else info won't find
	     its files (it uses the value of installation-directory).  */
	  tem = Fexpand_file_name (build_string ("info"), dir);
	  info_exists = Ffile_exists_p (tem);
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#else
	  info_exists = Qnil;
#endif
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	  if (!NILP (lib_src_exists) || !NILP (info_exists))
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	    {
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	      tem = Fexpand_file_name (build_string ("etc"), dir);
	      etc_exists = Ffile_exists_p (tem);
	      if (!NILP (etc_exists))
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		{
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		  Vinstallation_directory
		    = Ffile_name_as_directory (dir);
		  break;
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		}
	    }

	  /* See if dir's parent contains those subdirs.  */
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	  tem = Fexpand_file_name (build_string ("../lib-src"), dir);
	  lib_src_exists = Ffile_exists_p (tem);
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#ifdef MSDOS
	  /* See the MSDOS commentary above.  */
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	  tem = Fexpand_file_name (build_string ("../info"), dir);
	  info_exists = Ffile_exists_p (tem);
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#else
	  info_exists = Qnil;
#endif
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	  if (!NILP (lib_src_exists) || !NILP (info_exists))
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	    {
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	      tem = Fexpand_file_name (build_string ("../etc"), dir);
	      etc_exists = Ffile_exists_p (tem);
	      if (!NILP (etc_exists))
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		{
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		  tem = Fexpand_file_name (build_string (".."), dir);
		  Vinstallation_directory
		    = Ffile_name_as_directory (tem);
		  break;
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		}
	    }

	  /* If the Emacs executable is actually a link,
	     next try the dir that the link points into.  */
	  tem = Ffile_symlink_p (name);
	  if (!NILP (tem))
	    {
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	      name = Fexpand_file_name (tem, dir);
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	      dir = Ffile_name_directory (name);
	    }
	  else
	    break;
	}
    }

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  Vcommand_line_args = Qnil;

  for (i = argc - 1; i >= 0; i--)
    {
      if (i == 0 || i > skip_args)
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	/* For the moment, we keep arguments as is in unibyte strings.
	   They are decoded in the function command-line after we know
	   locale-coding-system.  */
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	Vcommand_line_args
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	  = Fcons (build_unibyte_string (argv[i]), Vcommand_line_args);
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    }
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  unbind_to (count, Qnil);
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}
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DEFUN ("invocation-name", Finvocation_name, Sinvocation_name, 0, 0, 0,
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       doc: /* Return the program name that was used to run Emacs.
Any directory names are omitted.  */)
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  (void)
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{
  return Fcopy_sequence (Vinvocation_name);
}

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DEFUN ("invocation-directory", Finvocation_directory, Sinvocation_directory,
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       0, 0, 0,
       doc: /* Return the directory name in which the Emacs executable was located.  */)
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  (void)
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{
  return Fcopy_sequence (Vinvocation_directory);
}

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588

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/* Test whether the next argument in ARGV matches SSTR or a prefix of
   LSTR (at least MINLEN characters).  If so, then if VALPTR is non-null
   (the argument is supposed to have a value) store in *VALPTR either
   the next argument or the portion of this one after the equal sign.
   ARGV is read starting at position *SKIPPTR; this index is advanced
   by the number of arguments used.

   Too bad we can't just use getopt for all of this, but we don't have
   enough information to do it right.  */
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static bool
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argmatch (char **argv, int argc, const char *sstr, const char *lstr,
          int minlen, char **valptr, int *skipptr)
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{
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  char *p = NULL;
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  ptrdiff_t arglen;
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  char *arg;

  /* Don't access argv[argc]; give up in advance.  */
  if (argc <= *skipptr + 1)
    return 0;

  arg = argv[*skipptr+1];
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  if (arg == NULL)
    return 0;
  if (strcmp (arg, sstr) == 0)
    {
      if (valptr != NULL)
	{
	  *valptr = argv[*skipptr+2];
	  *skipptr += 2;
	}
      else
	*skipptr += 1;
      return 1;
    }
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  arglen = (valptr != NULL && (p = strchr (arg, '=')) != NULL
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	    ? p - arg : strlen (arg));
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  if (lstr == 0 || arglen < minlen || strncmp (arg, lstr, arglen) != 0)
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    return 0;
  else if (valptr == NULL)
    {
      *skipptr += 1;
      return 1;
    }
  else if (p != NULL)
    {
      *valptr = p+1;
      *skipptr += 1;
      return 1;
    }
  else if (argv[*skipptr+2] != NULL)
    {
      *valptr = argv[*skipptr+2];
      *skipptr += 2;
      return 1;
    }
  else
    {
      return 0;
    }
}

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/* Close standard output and standard error, reporting any write
   errors as best we can.  This is intended for use with atexit.  */
static void
close_output_streams (void)
{
  if (close_stream (stdout) != 0)
    {
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      emacs_perror ("Write error to standard output");
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      _exit (EXIT_FAILURE);
    }

   if (close_stream (stderr) != 0)
     _exit (EXIT_FAILURE);
}
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/* ARGSUSED */
int
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main (int argc, char **argv)
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{
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  Lisp_Object dummy;
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  char stack_bottom_variable;
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  bool do_initial_setlocale;
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  bool dumping;
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  int skip_args = 0;
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  bool no_loadup = false;
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  char *junk = 0;
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  char *dname_arg = 0;
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#ifdef DAEMON_MUST_EXEC
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  char dname_arg2[80];
#endif
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  char *ch_to_dir = 0;
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  /* If we use --chdir, this records the original directory.  */
  char *original_pwd = 0;

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  stack_base = &dummy;

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  dumping = !initialized && (strcmp (argv[argc - 1], "dump") == 0
			     || strcmp (argv[argc - 1], "bootstrap") == 0);

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  /* True if address randomization interferes with memory allocation.  */
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# ifdef __PPC64__
  bool disable_aslr = true;
# else
  bool disable_aslr = dumping;
# endif

  if (disable_aslr && disable_address_randomization ())
    {
      /* Set this so the personality will be reverted before execs
	 after this one.  */
      xputenv ("EMACS_HEAP_EXEC=true");

      /* Address randomization was enabled, but is now disabled.
	 Re-execute Emacs to get a clean slate.  */
      execvp (argv[0], argv);

      /* If the exec fails, warn and then try anyway.  */
      perror (argv[0]);
    }

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#ifndef CANNOT_DUMP
  might_dump = !initialized;
#endif

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#ifdef GNU_LINUX
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  if (!initialized)
    {
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      char *heap_start = my_heap_start ();
      heap_bss_diff = heap_start - max (my_endbss, my_endbss_static);
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    }
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#endif
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#if defined WINDOWSNT || defined HAVE_NTGUI
  /* Set global variables used to detect Windows version.  Do this as
     early as possible.  (unexw32.c calls this function as well, but
     the additional call here is harmless.) */
  cache_system_info ();
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#ifdef WINDOWSNT
  /* On Windows 9X, we have to load UNICOWS.DLL as early as possible,
     to have non-stub implementations of APIs we need to convert file
     names between UTF-8 and the system's ANSI codepage.  */
  maybe_load_unicows_dll ();
#endif
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  /* This has to be done before module_init is called below, so that
     the latter could use the thread ID of the main thread.  */
  w32_init_main_thread ();
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#endif

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#ifdef RUN_TIME_REMAP
  if (initialized)
    run_time_remap (argv[0]);
#endif

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/* If using unexmacosx.c (set by s/darwin.h), we must do this. */
#ifdef DARWIN_OS
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  if (!initialized)
    unexec_init_emacs_zone ();
#endif

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  init_standard_fds ();
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  atexit (close_output_streams);

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#ifdef HAVE_MODULES
  module_init ();
#endif

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  sort_args (argc, argv);
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  argc = 0;
  while (argv[argc]) argc++;
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  if (argmatch (argv, argc, "-version", "--version", 3, NULL, &skip_args))
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    {
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      const char *version, *copyright;
      if (initialized)
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	{
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	  Lisp_Object tem, tem2;
	  tem = Fsymbol_value (intern_c_string ("emacs-version"));
	  tem2 = Fsymbol_value (intern_c_string ("emacs-copyright"));
	  if (!STRINGP (tem))
	    {
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	      fprintf (stderr, "Invalid value of 'emacs-version'\n");
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	      exit (1);
	    }
	  if (!STRINGP (tem2))
	    {
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	      fprintf (stderr, "Invalid value of 'emacs-copyright'\n");
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	      exit (1);
	    }
	  else
	    {
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	      version = SSDATA (tem);
	      copyright = SSDATA (tem2);
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	    }
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	}
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      else
	{
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	  version = emacs_version;
	  copyright = emacs_copyright;
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	}
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      printf ("%s %s\n", PACKAGE_NAME, version);
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      printf ("%s\n", copyright);
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      printf ("%s comes with ABSOLUTELY NO WARRANTY.\n", PACKAGE_NAME);
      printf ("You may redistribute copies of %s\n", PACKAGE_NAME);
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      printf ("under the terms of the GNU General Public License.\n");
      printf ("For more information about these matters, ");
      printf ("see the file named COPYING.\n");
      exit (0);
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    }
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  if (argmatch (argv, argc, "-chdir", "--chdir", 4, &ch_to_dir, &skip_args))
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    {
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#ifdef WINDOWSNT
      /* argv[] array is kept in its original ANSI codepage encoding,
	 we need to convert to UTF-8, for chdir to work.  */
      char newdir[MAX_UTF8_PATH];

      filename_from_ansi (ch_to_dir, newdir);
      ch_to_dir = newdir;
#endif
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      original_pwd = emacs_get_current_dir_name ();
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      if (chdir (ch_to_dir) != 0)
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        {
          fprintf (stderr, "%s: Can't chdir to %s: %s\n",
                   argv[0], ch_to_dir, strerror (errno));
          exit (1);
        }
    }
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#if defined (HAVE_SETRLIMIT) && defined (RLIMIT_STACK) && !defined (CYGWIN)
  /* Extend the stack space available.  Don't do that if dumping,
     since some systems (e.g. DJGPP) might define a smaller stack
     limit at that time.  And it's not needed on Cygwin, since emacs
     is built with an 8MB stack.  Moreover, the setrlimit call can
     cause problems on Cygwin
     (https://www.cygwin.com/ml/cygwin/2015-07/msg00096.html).  */
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  struct rlimit rlim;
  if (getrlimit (RLIMIT_STACK, &rlim) == 0
      && 0 <= rlim.rlim_cur && rlim.rlim_cur <= LONG_MAX)
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    {
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      rlim_t lim = rlim.rlim_cur;
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      /* Approximate the amount regex.c needs per unit of
	 re_max_failures, then add 33% to cover the size of the
	 smaller stacks that regex.c successively allocates and
	 discards on its way to the maximum.  */
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      int ratio = 20 * sizeof (char *);
      ratio += ratio / 3;
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      /* Extra space to cover what we're likely to use for other reasons.  */
      int extra = 200000;

      bool try_to_grow_stack = true;
#ifndef CANNOT_DUMP
      try_to_grow_stack = !noninteractive || initialized;
#endif

      if (try_to_grow_stack)
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	{
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	  rlim_t newlim = re_max_failures * ratio + extra;
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	  /* Round the new limit to a page boundary; this is needed
	     for Darwin kernel 15.4.0 (see Bug#23622) and perhaps
	     other systems.  Do not shrink the stack and do not exceed
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	     rlim_max.  Don't worry about exact values of
	     RLIM_INFINITY etc. since in practice when they are
	     nonnegative they are so large that the code does the
	     right thing anyway.  */
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	  long pagesize = getpagesize ();
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	  newlim += pagesize - 1;
	  if (0 <= rlim.rlim_max && rlim.rlim_max < newlim)
	    newlim = rlim.rlim_max;
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	  newlim -= newlim % pagesize;

	  if (pagesize <= newlim - lim)
	    {
	      rlim.rlim_cur = newlim;
	      if (setrlimit (RLIMIT_STACK, &rlim) == 0)
		lim = newlim;
	    }
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	}
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      /* Don't let regex.c overflow the stack.  */
      re_max_failures = lim < extra ? 0 : min (lim - extra, SIZE_MAX) / ratio;
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    }
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#endif /* HAVE_SETRLIMIT and RLIMIT_STACK and not CYGWIN */
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  /* Record (approximately) where the stack begins.  */
  stack_bottom = &stack_bottom_variable;

  clearerr (stdin);
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  emacs_backtrace (-1);

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#if !defined SYSTEM_MALLOC && !defined HYBRID_MALLOC
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  /* Arrange to get warning messages as memory fills up.  */
  memory_warnings (0, malloc_warning);
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  /* Call malloc at least once, to run malloc_initialize_hook.
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     Also call realloc and free for consistency.  */
  free (realloc (malloc (4), 4));
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#endif	/* not SYSTEM_MALLOC and not HYBRID_MALLOC */
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#ifdef MSDOS
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  SET_BINARY (fileno (stdin));
  fflush (stdout);
  SET_BINARY (fileno (stdout));
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#endif /* MSDOS */

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  /* Skip initial setlocale if LC_ALL is "C", as it's not needed in that case.
     The build procedure uses this while dumping, to ensure that the
     dumped Emacs does not have its system locale tables initialized,
     as that might cause screwups when the dumped Emacs starts up.  */
  {
    char *lc_all = getenv ("LC_ALL");
    do_initial_setlocale = ! lc_all || strcmp (lc_all, "C");
  }

  /* Set locale now, so that initial error messages are localized properly.
     fixup_locale must wait until later, since it builds strings.  */
  if (do_initial_setlocale)
    setlocale (LC_ALL, "");
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  text_quoting_flag = using_utf8 ();
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  inhibit_window_system = 0;

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  /* Handle the -t switch, which specifies filename to use as terminal.  */
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  while (1)
    {
      char *term;
      if (argmatch (argv, argc, "-t", "--terminal", 4, &term, &skip_args))
	{
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	  emacs_close (STDIN_FILENO);
	  emacs_close (STDOUT_FILENO);
	  int result = emacs_open (term, O_RDWR, 0);
	  if (result != STDIN_FILENO
	      || (fcntl (STDIN_FILENO, F_DUPFD_CLOEXEC, STDOUT_FILENO)
		  != STDOUT_FILENO))
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	    {
	      char *errstring = strerror (errno);
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	      fprintf (stderr, "%s: %s: %s\n", argv[0], term, errstring);
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	      exit (EXIT_FAILURE);
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	    }
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	  if (! isatty (STDIN_FILENO))
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	    {
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	      fprintf (stderr, "%s: %s: not a tty\n", argv[0], term);
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	      exit (EXIT_FAILURE);
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	    }
	  fprintf (stderr, "Using %s\n", term);
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#ifdef HAVE_WINDOW_SYSTEM
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	  inhibit_window_system = true; /* -t => -nw */
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#endif
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	}
      else
	break;
    }

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  /* Command line option --no-windows is deprecated and thus not mentioned
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     in the manual and usage information.  */
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  if (argmatch (argv, argc, "-nw", "--no-window-system", 6, NULL, &skip_args)
      || argmatch (argv, argc, "-nw", "--no-windows", 6, NULL, &skip_args))
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    inhibit_window_system = 1;
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  /* Handle the -batch switch, which means don't do interactive display.  */
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  noninteractive = 0;
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  if (argmatch (argv, argc, "-batch", "--batch", 5, NULL, &skip_args))
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    {
      noninteractive = 1;
      Vundo_outer_limit = Qnil;
    }
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  if (argmatch (argv, argc, "-script", "--script", 3, &junk, &skip_args))
    {
      noninteractive = 1;	/* Set batch mode.  */
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      /* Convert --script to -scriptload, un-skip it, and sort again
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	 so that it will be handled in proper sequence.  */
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      /* FIXME broken for --script=FILE - is that supposed to work?  */
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      argv[skip_args - 1] = (char *) "-scriptload";
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      skip_args -= 2;
      sort_args (argc, argv);
    }
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  /* Handle the --help option, which gives a usage message.  */
975
  if (argmatch (argv, argc, "-help", "--help", 3, NULL, &skip_args))
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    {
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      int i;
      printf ("Usage: %s [OPTION-OR-FILENAME]...\n", argv[0]);
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      for (i = 0; i < ARRAYELTS (usage_message); i++)
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	fputs (usage_message[i], stdout);
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      exit (0);
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    }

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  daemon_type = 0;

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#ifndef WINDOWSNT
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  /* Make sure IS_DAEMON starts up as false.  */
  daemon_pipe[1] = 0;
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#else
  w32_daemon_event = NULL;
#endif
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  int sockfd = -1;

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  if (argmatch (argv, argc, "-new-daemon", "--new-daemon", 10, NULL, &skip_args)
      || argmatch (argv, argc, "-new-daemon", "--new-daemon", 10, &dname_arg, &skip_args))
    {
      daemon_type = 1;           /* foreground */
    }
  else if (argmatch (argv, argc, "-daemon", "--daemon", 5, NULL, &skip_args)
      || argmatch (argv, argc, "-daemon", "--daemon", 5, &dname_arg, &skip_args)
      || argmatch (argv, argc, "-old-daemon", "--old-daemon", 10, NULL, &skip_args)
      || argmatch (argv, argc, "-old-daemon", "--old-daemon", 10, &dname_arg, &skip_args))
    {
      daemon_type = 2;          /* background */
    }


  if (daemon_type > 0)
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    {
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#ifndef DOS_NT
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      if (daemon_type == 2)
        {
          /* Start as a background daemon: fork a new child process which
             will run the rest of the initialization code, then exit.

             Detaching a daemon requires the following steps:
             - fork
             - setsid
             - exit the parent
             - close the tty file-descriptors

             We only want to do the last 2 steps once the daemon is ready to
             serve requests, i.e. after loading .emacs (initialization).
             OTOH initialization may start subprocesses (e.g. ispell) and these
             should be run from the proper process (the one that will end up
             running as daemon) and with the proper "session id" in order for
             them to keep working after detaching, so fork and setsid need to be
             performed before initialization.

             We want to avoid exiting before the server socket is ready, so
             use a pipe for synchronization.  The parent waits for the child
             to close its end of the pipe (using `daemon-initialized')
             before exiting.  */
          if (emacs_pipe (daemon_pipe) != 0)
            {
              fprintf (stderr, "Cannot pipe!\n");
              exit (1);
            }
        } /* daemon_type == 2 */
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1043
#ifdef HAVE_LIBSYSTEMD
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      /* Read the number of sockets passed through by systemd.  */
      int systemd_socket = sd_listen_fds (1);
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      if (systemd_socket > 1)
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        fprintf (stderr,
		 ("\n"
		  "Warning: systemd passed more than one socket to Emacs.\n"
		  "Try 'Accept=false' in the Emacs socket unit file.\n"));
      else if (systemd_socket == 1
	       && (0 < sd_is_socket (SD_LISTEN_FDS_START,
				     AF_UNSPEC, SOCK_STREAM, 1)))
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	sockfd = SD_LISTEN_FDS_START;
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#endif /* HAVE_LIBSYSTEMD */

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#ifdef USE_GTK
      fprintf (stderr, "\nWarning: due to a long standing Gtk+ bug\nhttp://bugzilla.gnome.org/show_bug.cgi?id=85715\n\
Emacs might crash when run in daemon mode and the X11 connection is unexpectedly lost.\n\
Using an Emacs configured with --with-x-toolkit=lucid does not have this problem.\n");
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#endif /* USE_GTK */
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      if (daemon_type == 2)
        {
          pid_t f;
#ifndef DAEMON_MUST_EXEC
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          f = fork ();
#else /* DAEMON_MUST_EXEC */
          if (!dname_arg || !strchr (dname_arg, '\n'))
            f = fork ();  /* in orig */
          else
            f = 0;  /* in exec'd */
#endif /* !DAEMON_MUST_EXEC */
          if (f > 0)
            {
              int retval;
              char buf[1];

              /* Close unused writing end of the pipe.  */
              emacs_close (daemon_pipe[1]);

              /* Just wait for the child to close its end of the pipe.  */
              do
                {
                  retval = read (daemon_pipe[0], &buf, 1);
                }
              while (retval == -1 && errno == EINTR);

              if (retval < 0)
                {
                  fprintf (stderr, "Error reading status from child\n");
                  exit (1);
                }
              else if (retval == 0)
                {
                  fprintf (stderr, "Error: server did not start correctly\n");
                  exit (1);
                }

              emacs_close (daemon_pipe[0]);
              exit (0);
            }
          if (f < 0)
            {
              emacs_perror ("fork");
              exit (EXIT_CANCELED);
            }
1110

1111
#ifdef DAEMON_MUST_EXEC
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          {
            /* In orig process, forked as child, OR in exec'd. */
            if (!dname_arg || !strchr (dname_arg, '\n'))
              {  /* In orig, child: now exec w/special daemon name. */
                char fdStr[80];
                int fdStrlen =
                  snprintf (fdStr, sizeof fdStr,
                            "--old-daemon=\n%d,%d\n%s", daemon_pipe[0],
                            daemon_pipe[1], dname_arg ? dname_arg : "");

                if (! (0 <= fdStrlen && fdStrlen < sizeof fdStr))
                  {
                    fprintf (stderr, "daemon: child name too long\n");
                    exit (EXIT_CANNOT_INVOKE);
                  }

                argv[skip_args] = fdStr;

                fcntl (daemon_pipe[0], F_SETFD, 0);
                fcntl (daemon_pipe[1], F_SETFD, 0);
                execvp (argv[0], argv);