Add comments, restructure

app.json

@@ -1,12 +1,12 @@
 {
   "name": "Kaboom",
   "env": {
-    "REMOTE_KEY": {
-      "description": "Private key for reverse SSH",
+    "PROXY_KEY": {
+      "description": "Private key for proxy server",
       "required": true
     },
-    "SYNC_KEY": {
-      "description": "Private key for data sync",
+    "SCHEMATIC_KEY": {
+      "description": "Private key for schematic repository",
       "required": true
     }
   }

bin/compile

@@ -2,5 +2,15 @@
 BIN_DIR="$(cd "$(dirname "$0")" && pwd)"
 BUILD_DIR=$1
 
+# Build dtach for running server in background
+
+cd src/detach*
+./configure
+make
+mkdir $BUILD_DIR/detach/bin/
+mv detach $BUILD_DIR/detach/bin/
+
+# Set up scripts
+
 mv script $BUILD_DIR/script
 mv $BIN_DIR/start $BUILD_DIR/script/

bin/start

@@ -1,22 +1,25 @@
 #!/bin/sh
-PATH="$HOME/autossh/bin/:$HOME/java/bin/:$HOME/tmux/bin/:$HOME/ttyd/bin/:$PATH"
+PATH="$HOME/detach/bin/:$HOME/java/bin/:$PATH"
 
-echo "$REMOTE_KEY" > .ssh/remote
-echo "$SYNC_KEY" > .ssh/id_rsa
-chmod 600 .ssh/remote
+# Set up SSH for proxy server and schematics repository
+# Load keys from environmental variables
 
+echo "$PROXY_KEY" > .ssh/proxy
+chmod 600 .ssh/proxy
+
+echo "$SCHEMATIC_KEY" > .ssh/id_rsa
 ssh-keyscan github.com >> .ssh/known_hosts
 
-chmod -R 500 plugins/bStats/ plugins/PluginMetrics/
-
-git clone git@github.com:kaboomserver/schematics.git plugins/FastAsyncWorldEdit/schematics/
+# Run scripts for starting the Minecraft server, reverse proxy and schematic
+# checker in the background
 
 while true; do
-	tmux new -d -s server 'sh -c script/server' >/dev/null
-	tmux new -d -s remote 'sh -x script/remote' >/dev/null
-	#tmux new -d -s webconsole 'sh -x script/webconsole' >/dev/null
-	tmux new -d -s schematics 'sh -x script/schematics' >/dev/null
+	dtach -n server 'sh -c script/server'
+	dtach -n proxy 'sh -x script/proxy'
+	dtach -n schematics 'sh -x script/schematics'
 	sleep 5
 done &
 
+# Keep this startup script alive to prevent Heroku from stopping the server
+
 sleep infinity

script/alivecheck

@@ -1,9 +1,17 @@
 #!/bin/sh
+
+# The following script is a failsafe for killing the Minecraft server if it happens
+# to be stuck
+
 while true; do
 	sleep 420
 	logfile=$HOME/logs/latest.log
 
 	if [ -f "$logfile" ]; then
+
+		# If localhost:25565 doesn't respond to ping, or if the log file is older than
+		# 3 minutes, kill the server
+
 		if [ "$(env printf '\xFE' | nc -w 5 localhost 25565 | wc -m)" -eq 0 ] ||
 			[ "$(( $(date +%s) - $(date -r $logfile +%s) ))" -gt 180 ]; then
 			if [ "$(tail -20 $logfile | grep -c 'ERROR]: Requested chunk')" -eq 1 ]; then

script/proxy

@@ -1,4 +1,9 @@
 #!/bin/sh
+
+# Since we can't open TCP ports on Heroku, we need to forward traffic to a proxy server that
+# permits incoming connections
+# Resources for setting up the proxy server: https://github.com/kaboomserver/proxy
+
 ssh -i ~/.ssh/remote \
 	-o StrictHostKeyChecking=no -o ExitOnForwardFailure=yes -o StreamLocalBindUnlink=yes \
 	-c aes128-ctr \

script/schematics

@@ -1,4 +1,10 @@
 #!/bin/sh
+
+# Schematics are saved in a separate git repository, which is cloned whenever Heroku starts
+# from a fresh state. Only non-existing files are added to the repository.
+
+git clone git@github.com:kaboomserver/schematics.git $HOME/plugins/FastAsyncWorldEdit/schematics/
+
 while true; do
 	cd $HOME/plugins/FastAsyncWorldEdit/schematics/
 	if [ "$(git add $(git ls-files -o) -v)" ]; then

script/server

@@ -1,9 +1,12 @@
 #!/bin/sh
+
+# The alive checker and Minecraft server is started at the same time. For performance reasons, the
+# OpenJ9 JVM is used instead of Java's default Hotspot JVM.
+
+chmod -R 500 $HOME/plugins/bStats/ $HOME/plugins/PluginMetrics/
+dtach -n alivecheck 'sh -x $HOME/script/alivecheck'
+
 while true; do
-	stty intr undef
-	unset TMUX
-	tmux new -d -s alivecheck 'sh -x script/alivecheck'
 	java -Xmx384M -Xtune:virtualized -Xaggressive -Xcompressedrefs -Xdump:none -Xgc:concurrentScavenge -Xgc:dnssExpectedTimeRatioMaximum=3 -Xgc:scvNoAdaptiveTenure -Xdisableexplicitgc -Xshareclasses -Xshareclasses:noPersistentDiskSpaceCheck -XX:-HeapDumpOnOutOfMemoryError -XX:OnOutofMemoryError="pkill -9 java" -XX:MaxDirectMemorySize=64M -XX:+UseContainerSupport -XX:+ClassRelationshipVerifier -Dpaper.playerconnection.keepalive=360 -DIReallyKnowWhatIAmDoingISwear -jar server.jar --world-dir=worlds
-	tmux kill-session -t alivecheck
 	sleep 1
 done

script/stop

@@ -1,2 +1,5 @@
 #!/bin/sh
+
+# Shutdown script for Paper/Spigot
+
 pkill -9 java

script/webconsole

@@ -1,7 +0,0 @@
-#!/bin/sh
-cd $HOME/plugins/FastAsyncWorldEdit/schematics/
-
-while true; do
-	python3 -m http.server $PORT --bind 0.0.0.0
-	sleep 1
-done

src/dtach-0.9/.gitignore

@@ -0,0 +1,11 @@
+# Files generated by configure
+
+/Makefile
+/config.h
+/config.log
+/config.status
+/configure.lineno
+
+# Files generated by make
+*.o
+/dtach

src/dtach-0.9/COPYING

@@ -0,0 +1,340 @@
+		    GNU GENERAL PUBLIC LICENSE
+		       Version 2, June 1991
+
+ Copyright (C) 1989, 1991 Free Software Foundation, Inc.
+     59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+ Everyone is permitted to copy and distribute verbatim copies
+ of this license document, but changing it is not allowed.
+
+			    Preamble
+
+  The licenses for most software are designed to take away your
+freedom to share and change it.  By contrast, the GNU General Public
+License is intended to guarantee your freedom to share and change free
+software--to make sure the software is free for all its users.  This
+General Public License applies to most of the Free Software
+Foundation's software and to any other program whose authors commit to
+using it.  (Some other Free Software Foundation software is covered by
+the GNU Library General Public License instead.)  You can apply it to
+your programs, too.
+
+  When we speak of free software, we are referring to freedom, not
+price.  Our General Public Licenses are designed to make sure that you
+have the freedom to distribute copies of free software (and charge for
+this service if you wish), that you receive source code or can get it
+if you want it, that you can change the software or use pieces of it
+in new free programs; and that you know you can do these things.
+
+  To protect your rights, we need to make restrictions that forbid
+anyone to deny you these rights or to ask you to surrender the rights.
+These restrictions translate to certain responsibilities for you if you
+distribute copies of the software, or if you modify it.
+
+  For example, if you distribute copies of such a program, whether
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+
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+(2) offer you this license which gives you legal permission to copy,
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+
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+that everyone understands that there is no warranty for this free
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+
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+
+  The precise terms and conditions for copying, distribution and
+modification follow.
+
+		    GNU GENERAL PUBLIC LICENSE
+   TERMS AND CONDITIONS FOR COPYING, DISTRIBUTION AND MODIFICATION
+
+  0. This License applies to any program or other work which contains
+a notice placed by the copyright holder saying it may be distributed
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+
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+
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+
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+
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+			    NO WARRANTY
+
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+
+		     END OF TERMS AND CONDITIONS
+
+	    How to Apply These Terms to Your New Programs
+
+  If you develop a new program, and you want it to be of the greatest
+possible use to the public, the best way to achieve this is to make it
+free software which everyone can redistribute and change under these terms.
+
+  To do so, attach the following notices to the program.  It is safest
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+
+    <one line to give the program's name and a brief idea of what it does.>
+    Copyright (C) <year>  <name of author>
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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.
+
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+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+
+
+Also add information on how to contact you by electronic and paper mail.
+
+If the program is interactive, make it output a short notice like this
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+
+    Gnomovision version 69, Copyright (C) year  name of author
+    Gnomovision comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+    This is free software, and you are welcome to redistribute it
+    under certain conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License.  Of course, the commands you use may
+be called something other than `show w' and `show c'; they could even be
+mouse-clicks or menu items--whatever suits your program.
+
+You should also get your employer (if you work as a programmer) or your
+school, if any, to sign a "copyright disclaimer" for the program, if
+necessary.  Here is a sample; alter the names:
+
+  Yoyodyne, Inc., hereby disclaims all copyright interest in the program
+  `Gnomovision' (which makes passes at compilers) written by James Hacker.
+
+  <signature of Ty Coon>, 1 April 1989
+  Ty Coon, President of Vice
+
+This General Public License does not permit incorporating your program into
+proprietary programs.  If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library.  If this is what you want to do, use the GNU Library General
+Public License instead of this License.

src/dtach-0.9/Makefile.in

@@ -0,0 +1,36 @@
+srcdir = @srcdir@
+CC = @CC@
+CFLAGS = @CFLAGS@ -I.
+LDFLAGS = @LDFLAGS@
+LIBS = @LIBS@
+VERSION = @PACKAGE_VERSION@
+VPATH = $(srcdir)
+
+OBJ = attach.o master.o main.o
+SRC = $(srcdir)/attach.c $(srcdir)/master.c $(srcdir)/main.c
+
+TARFILES = $(srcdir)/README $(srcdir)/COPYING $(srcdir)/Makefile.in \
+	   $(srcdir)/config.h.in $(SRC) \
+	   $(srcdir)/dtach.h $(srcdir)/dtach.spec $(srcdir)/configure \
+	   $(srcdir)/configure.ac $(srcdir)/dtach.1
+
+dtach: $(OBJ)
+	$(CC) -o $@ $(LDFLAGS) $(OBJ) $(LIBS)
+
+clean:
+	rm -f dtach $(OBJ) dtach-$(VERSION).tar.gz
+
+distclean: clean
+	rm -f config.h Makefile config.log config.status config.cache
+
+tar:
+	mkdir dtach-$(VERSION)
+	cp $(TARFILES) dtach-$(VERSION)
+	tar -cf dtach-$(VERSION).tar dtach-$(VERSION)/
+	gzip -9f dtach-$(VERSION).tar
+	rm -rf dtach-$(VERSION)
+
+attach.o: @srcdir@/attach.c @srcdir@/dtach.h config.h
+master.o: @srcdir@/master.c @srcdir@/dtach.h config.h
+main.o: @srcdir@/main.c @srcdir@/dtach.h config.h
+

src/dtach-0.9/README

@@ -0,0 +1,210 @@
+1. INTRODUCTION
+
+dtach is a program written in C that emulates the detach feature of
+screen, which allows a program to be executed in an environment that is
+protected from the controlling terminal. For instance, the program under
+the control of dtach would not be affected by the terminal being
+disconnected for some reason.
+
+dtach was written because screen did not adequately meet my needs; I did
+not need screen's extra features, such as support for multiple
+terminals or terminal emulation support. screen was also too big,
+bulky, and had source code that was difficult to understand.
+
+screen also interfered with my use of full-screen applications such as
+emacs and ircII, due to its excessive interpretation of the stream between
+the program and the attached terminals. dtach does not have a terminal
+emulation layer, and passes the raw output stream of the program to the
+attached terminals. The only input processing that dtach does perform is
+scanning for the detach character (which signals dtach to detach from
+the program) and processing the suspend key (which tells dtach to
+temporarily suspend itself without affecting the running program), and both
+of these can both be disabled if desired.
+
+Contrary to screen, dtach has minimal features, and is extremely tiny.
+This allows dtach to be more easily audited for bugs and security
+holes, and makes it accessible in environments where space is limited,
+such as on rescue disks.
+
+dtach has only been tested on the Linux/x86 platform, however it should
+be easily portable to other variants of Unix. It currently assumes that
+the host system uses POSIX termios, and has a working forkpty function
+available.
+
+dtach may need access to various devices in the filesystem depending on what
+forkpty does. For example, dtach on Linux usually needs access to /dev/ptmx
+and /dev/pts.
+
+2. QUICK START
+
+Compiling dtach should be simple, as it uses autoconf:
+
+	$ ./configure
+	$ make
+
+If all goes well, a dtach binary should be built for your system. You can
+then copy it to the appropriate place on your system.
+
+dtach uses Unix-domain sockets to represent sessions; these are network
+sockets that are stored in the filesystem. You specify the name of the
+socket that dtach should use when creating or attaching to dtach sessions.
+
+For example, let's create a new session that is running ircII. We will use
+/tmp/foozle as the session's socket:
+
+	$ dtach -A /tmp/foozle irc RuneB irc.freenode.net
+
+Here, -A tells dtach to either create a new session or attach to the
+existing session. If the session at /tmp/foozle does not exist yet, the
+program will be executed. If it does exist, then dtach will attach to
+the existing session.
+
+dtach has another attach mode, which is specified by using -a. The -a
+mode attaches to an already existing session, but will not create a new
+session. Each attaching process can have a separate detach character,
+suspend behavior, and redraw method, which are explained in the
+following sections.
+
+dtach is able to attach to the same session multiple times, though you
+will likely encounter problems if your terminals have different window
+sizes. Pressing ^L (Ctrl-L) will reset the window size of the program to
+match the current terminal.
+
+dtach also has a mode that copies the contents of standard input to a session.
+For example:
+
+	$ echo -ne 'cd /var/log\nls -l\n' | dtach -p /tmp/foozle
+
+The contents are sent verbatim including any embedded control characters (e.g.
+the newline characters in the above example), and dtach will not scan the
+input for a detach character.
+
+3. DETACHING FROM THE SESSION
+
+By default, dtach scans the keyboard input looking for the detach character.
+When the detach character is pressed, dtach will detach from the current
+session and exit, leaving the program running in the background. You can then
+re-attach to the program by running dtach again with -A or -a.
+
+The default detach character is ^\ (Ctrl-\). This can be changed by supplying
+the -e option to dtach when attaching. For example:
+
+	$ dtach -a /tmp/foozle -e '^A'
+
+That command would attach to the existing session at /tmp/foozle and use
+^A (Ctrl-A) as the detach character, instead of the default ^\.
+
+You can disable processing of the detach character by supplying the -E
+option to dtach when attaching.
+
+4. SUSPENDING DTACH
+
+By default, dtach also processes the suspend key (^Z or Ctrl-Z) itself,
+instead of passing it to the program. Thus, pressing suspend only suspends
+the attaching process, instead of the running program. This can be very
+useful for applications such as ircII, where you may not necessarily want
+the program to be suspended.
+
+Processing of the suspend key can be disabled by supplying the -z option
+to dtach when attaching.
+
+5. REDRAW METHOD
+
+When attaching, dtach can use one of three methods to redraw the screen
+(none, ctrl_l, or winch). By default, dtach uses the ctrl_l method,
+which simply sends a ^L (Ctrl-L) character to the program if the
+terminal is in character-at-a-time and no-echo mode. The winch method
+forces a WINCH signal to be sent to the program, and the none method
+disables redrawing completely.
+
+For example, this command tells dtach to attach to a session at
+/tmp/foozle and use the winch redraw method:
+
+	$ dtach -a /tmp/foozle -r winch
+
+When creating a new session (with the -c or -A modes), the specified
+method is used as the default redraw method for the session.
+
+6. CHANGES
+
+The changes in version 0.9 are:
+- Added AIX support.
+- Added dtach -N, a mode similar to dtach -n, except dtach will stay in the
+  foreground instead of daemonizing.
+- Added dtach -p, which copies the contents of standard input to a session.
+- dtach will no longer send 255 bytes of garbage to the program when read()
+  returns an error.
+- The executable bit is now set on the socket if clients are attached, and
+  cleared when all clients have detached.
+- The initial state of signals such as SIGPIPE are now preserved when
+  executing the program, instead of having the program start with some signals
+  ignored.
+- A buffer overflow no longer occurs when a long socket path name is used, and
+  dtach will now try to use chdir to get around the length limitation if
+  necessary.
+
+The changes in version 0.8 are:
+- When using dtach -A or dtach -c, the master will now wait until the client
+  attaches before trying to read from the program being executed. This avoids
+  a race condition when the program prints something and exits before the
+  client can attach itself.
+- Instead of exiting quietly, dtach will now report any errors that occur
+  while trying to execute the program.
+- dtach -n can now be used without a terminal.
+- dtach -A will now try to detect and remove stale sockets.
+- Removed a Linux-specific escape sequence from the code that restores the
+  original terminal settings.
+- Changed dtach.1 to use \- for the dashes in command line options, and
+  fix an ambiguous backslash.
+- Use non-blocking mode in the master process, and avoid data loss by ensuring
+  that at least one attaching client succesfully completes a write.
+- Fix -e ^<char> to work with lowercase characters.
+
+The changes in version 0.7 are:
+- The redraw method can now be explicitly specified on the command line
+  (either no redraw at all, the old ^L character method, and the new WINCH
+  signal method), since many programs only handle one or the other properly.
+- Changed the default redraw method back to the old ^L character method.
+- Changed the attach code to check the return value of select more carefully.
+- Changed the SIGWINCH handler to reinstall itself, to handle systems that
+  always reset the handler.
+- Added more proper process group handling.
+
+The changes in version 0.6 are:
+- Redraws are now handled by sending the child process a WINCH signal instead
+  of by sending a ^L character. This should help prevent line-oriented
+  programs (such as bash) from clearing the screen excessively.
+- Flow control is now disabled when setting raw mode on the terminal.
+- Switched to using select instead of poll.
+- Changed some exits to exit succesfully instead of non-sucessfully.
+- Updated my email address.
+- Updated to Autoconf 2.59, renaming some files in the process.
+
+The changes in version 0.5 are:
+- Fix fd leakage.
+- Prevent atexit from being called twice on dtach -A.
+
+The changes in version 0.4 are:
+- Slightly improved README and dtach.1
+- Portability updates thanks to sourceforge's compile farm. dtach should now
+  work on: FreeBSD, Debian/alpha, Debian/sparc, Debian/PPC, and Solaris.
+
+The changes in version 0.3 are:
+- Fixed a typo in dtach.1
+- Changed the attach code so that it tells the master when a suspend
+  occurs.
+- Decreased the client <-> master packet size.
+- Changed the master to send a stream of text to attaching clients
+  instead of sending a huge packet all the time.
+- Use getrlimit and dynamically allocate the data structures, if
+  possible.
+- Added some more autoconf checks.
+- Initial sourceforge release.
+ 
+7. AUTHOR
+
+dtach is (C)Copyright 2004-2016 Ned T. Crigler, and is under the GNU General
+Public License.
+
+Comments and suggestions about dtach are welcome, and can be sent to
+the author at: <crigler@users.sourceforge.net>.

src/dtach-0.9/attach.c

@@ -0,0 +1,361 @@
+/*
+    dtach - A simple program that emulates the detach feature of screen.
+    Copyright (C) 2004-2016 Ned T. Crigler
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+#include "dtach.h"
+
+#ifndef VDISABLE
+#ifdef _POSIX_VDISABLE
+#define VDISABLE _POSIX_VDISABLE
+#else
+#define VDISABLE 0377
+#endif
+#endif
+
+/*
+** The current terminal settings. After coming back from a suspend, we
+** restore this.
+*/
+static struct termios cur_term;
+/* 1 if the window size changed */
+static int win_changed;
+
+/* Restores the original terminal settings. */
+static void
+restore_term(void)
+{
+	tcsetattr(0, TCSADRAIN, &orig_term);
+
+	/* Make cursor visible. Assumes VT100. */
+	printf("\033[?25h");
+	fflush(stdout);
+}
+
+/* Connects to a unix domain socket */
+static int
+connect_socket(char *name)
+{
+	int s;
+	struct sockaddr_un sockun;
+
+	if (strlen(name) > sizeof(sockun.sun_path) - 1)
+	{
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+
+	s = socket(PF_UNIX, SOCK_STREAM, 0);
+	if (s < 0)
+		return -1;
+	sockun.sun_family = AF_UNIX;
+	strcpy(sockun.sun_path, name);
+	if (connect(s, (struct sockaddr*)&sockun, sizeof(sockun)) < 0)
+	{
+		close(s);
+
+		/* ECONNREFUSED is also returned for regular files, so make
+		** sure we are trying to connect to a socket. */
+		if (errno == ECONNREFUSED)
+		{
+			struct stat st;
+
+			if (stat(name, &st) < 0)
+				return -1;
+			else if (!S_ISSOCK(st.st_mode) || S_ISREG(st.st_mode))
+				errno = ENOTSOCK;
+		}
+		return -1;
+	}
+	return s;
+}
+
+/* Signal */
+static RETSIGTYPE
+die(int sig)
+{
+	/* Print a nice pretty message for some things. */
+	if (sig == SIGHUP || sig == SIGINT)
+		printf(EOS "\r\n[detached]\r\n");
+	else
+		printf(EOS "\r\n[got signal %d - dying]\r\n", sig);
+	exit(1);
+}
+
+/* Window size change. */
+static RETSIGTYPE
+win_change()
+{
+	signal(SIGWINCH, win_change);
+	win_changed = 1;
+}
+
+/* Handles input from the keyboard. */
+static void
+process_kbd(int s, struct packet *pkt)
+{
+	/* Suspend? */
+	if (!no_suspend && (pkt->u.buf[0] == cur_term.c_cc[VSUSP]))
+	{
+		/* Tell the master that we are suspending. */
+		pkt->type = MSG_DETACH;
+		write(s, pkt, sizeof(struct packet));
+
+		/* And suspend... */
+		tcsetattr(0, TCSADRAIN, &orig_term);
+		printf(EOS "\r\n");
+		kill(getpid(), SIGTSTP);
+		tcsetattr(0, TCSADRAIN, &cur_term);
+
+		/* Tell the master that we are returning. */
+		pkt->type = MSG_ATTACH;
+		write(s, pkt, sizeof(struct packet));
+
+		/* We would like a redraw, too. */
+		pkt->type = MSG_REDRAW;
+		pkt->len = redraw_method;
+		ioctl(0, TIOCGWINSZ, &pkt->u.ws);
+		write(s, pkt, sizeof(struct packet));
+		return;
+	}
+	/* Detach char? */
+	else if (pkt->u.buf[0] == detach_char)
+	{
+		printf(EOS "\r\n[detached]\r\n");
+		exit(0);
+	}
+	/* Just in case something pukes out. */
+	else if (pkt->u.buf[0] == '\f')
+		win_changed = 1;
+
+	/* Push it out */
+	write(s, pkt, sizeof(struct packet));
+}
+
+int
+attach_main(int noerror)
+{
+	struct packet pkt;
+	unsigned char buf[BUFSIZE];
+	fd_set readfds;
+	int s;
+
+	/* Attempt to open the socket. Don't display an error if noerror is 
+	** set. */
+	s = connect_socket(sockname);
+	if (s < 0 && errno == ENAMETOOLONG)
+	{
+		char *slash = strrchr(sockname, '/');
+
+		/* Try to shorten the socket's path name by using chdir. */
+		if (slash)
+		{
+			int dirfd = open(".", O_RDONLY);
+
+			if (dirfd >= 0)
+			{
+				*slash = '\0';
+				if (chdir(sockname) >= 0)
+				{
+					s = connect_socket(slash + 1);
+					fchdir(dirfd);
+				}
+				*slash = '/';
+				close(dirfd);
+			}
+		}
+	}
+	if (s < 0)
+	{
+		if (!noerror)
+			printf("%s: %s: %s\n", progname, sockname,
+				strerror(errno));
+		return 1;
+	}
+
+	/* The current terminal settings are equal to the original terminal
+	** settings at this point. */
+	cur_term = orig_term;
+
+	/* Set a trap to restore the terminal when we die. */
+	atexit(restore_term);
+
+	/* Set some signals. */
+	signal(SIGPIPE, SIG_IGN);
+	signal(SIGXFSZ, SIG_IGN);
+	signal(SIGHUP, die);
+	signal(SIGTERM, die);
+	signal(SIGINT, die);
+	signal(SIGQUIT, die);
+	signal(SIGWINCH, win_change);
+
+	/* Set raw mode. */
+	cur_term.c_iflag &= ~(IGNBRK|BRKINT|PARMRK|ISTRIP|INLCR|IGNCR|ICRNL);
+	cur_term.c_iflag &= ~(IXON|IXOFF);
+	cur_term.c_oflag &= ~(OPOST);
+	cur_term.c_lflag &= ~(ECHO|ECHONL|ICANON|ISIG|IEXTEN);
+	cur_term.c_cflag &= ~(CSIZE|PARENB);
+	cur_term.c_cflag |= CS8;
+	cur_term.c_cc[VLNEXT] = VDISABLE;
+	cur_term.c_cc[VMIN] = 1;
+	cur_term.c_cc[VTIME] = 0;
+	tcsetattr(0, TCSADRAIN, &cur_term);
+
+	/* Clear the screen. This assumes VT100. */
+	write(1, "\33[H\33[J", 6);
+
+	/* Tell the master that we want to attach. */
+	memset(&pkt, 0, sizeof(struct packet));
+	pkt.type = MSG_ATTACH;
+	write(s, &pkt, sizeof(struct packet));
+
+	/* We would like a redraw, too. */
+	pkt.type = MSG_REDRAW;
+	pkt.len = redraw_method;
+	ioctl(0, TIOCGWINSZ, &pkt.u.ws);
+	write(s, &pkt, sizeof(struct packet));
+
+	/* Wait for things to happen */
+	while (1)
+	{
+		int n;
+
+		FD_ZERO(&readfds);
+		FD_SET(0, &readfds);
+		FD_SET(s, &readfds);
+		n = select(s + 1, &readfds, NULL, NULL, NULL);
+		if (n < 0 && errno != EINTR && errno != EAGAIN)
+		{
+			printf(EOS "\r\n[select failed]\r\n");
+			exit(1);
+		}
+
+		/* Pty activity */
+		if (n > 0 && FD_ISSET(s, &readfds))
+		{
+			ssize_t len = read(s, buf, sizeof(buf));
+
+			if (len == 0)
+			{
+				printf(EOS "\r\n[EOF - dtach terminating]"
+					"\r\n");
+				exit(0);
+			}
+			else if (len < 0)
+			{
+				printf(EOS "\r\n[read returned an error]\r\n");
+				exit(1);
+			}
+			/* Send the data to the terminal. */
+			write(1, buf, len);
+			n--;
+		}
+		/* stdin activity */
+		if (n > 0 && FD_ISSET(0, &readfds))
+		{
+			ssize_t len;
+
+			pkt.type = MSG_PUSH;
+			memset(pkt.u.buf, 0, sizeof(pkt.u.buf));
+			len = read(0, pkt.u.buf, sizeof(pkt.u.buf));
+
+			if (len <= 0)
+				exit(1);
+
+			pkt.len = len;
+			process_kbd(s, &pkt);
+			n--;
+		}
+
+		/* Window size changed? */
+		if (win_changed)
+		{
+			win_changed = 0;
+
+			pkt.type = MSG_WINCH;
+			ioctl(0, TIOCGWINSZ, &pkt.u.ws);
+			write(s, &pkt, sizeof(pkt));
+		}
+	}
+	return 0;
+}
+
+int
+push_main()
+{
+	struct packet pkt;
+	int s;
+
+	/* Attempt to open the socket. */
+	s = connect_socket(sockname);
+	if (s < 0 && errno == ENAMETOOLONG)
+	{
+		char *slash = strrchr(sockname, '/');
+
+		/* Try to shorten the socket's path name by using chdir. */
+		if (slash)
+		{
+			int dirfd = open(".", O_RDONLY);
+
+			if (dirfd >= 0)
+			{
+				*slash = '\0';
+				if (chdir(sockname) >= 0)
+				{
+					s = connect_socket(slash + 1);
+					fchdir(dirfd);
+				}
+				*slash = '/';
+				close(dirfd);
+			}
+		}
+	}
+	if (s < 0)
+	{
+		printf("%s: %s: %s\n", progname, sockname, strerror(errno));
+		return 1;
+	}
+
+	/* Set some signals. */
+	signal(SIGPIPE, SIG_IGN);
+
+	/* Push the contents of standard input to the socket. */
+	pkt.type = MSG_PUSH;
+	for (;;)
+	{
+		ssize_t len;
+
+		memset(pkt.u.buf, 0, sizeof(pkt.u.buf));
+		len = read(0, pkt.u.buf, sizeof(pkt.u.buf));
+
+		if (len == 0)
+			return 0;
+		else if (len < 0)
+		{
+			printf("%s: %s: %s\n", progname, sockname,
+			       strerror(errno));
+			return 1;
+		}
+
+		pkt.len = len;
+		if (write(s, &pkt, sizeof(struct packet)) < 0)
+		{
+			printf("%s: %s: %s\n", progname, sockname,
+			       strerror(errno));
+			return 1;
+		}
+	}
+}

src/dtach-0.9/config.h.in

@@ -0,0 +1,136 @@
+/* config.h.in.  Generated from configure.ac by autoheader.  */
+
+/* Define to 1 if you have the `atexit' function. */
+#undef HAVE_ATEXIT
+
+/* Define to 1 if you have the `dup2' function. */
+#undef HAVE_DUP2
+
+/* Define to 1 if you have the <fcntl.h> header file. */
+#undef HAVE_FCNTL_H
+
+/* Define to 1 if you have the `forkpty' function. */
+#undef HAVE_FORKPTY
+
+/* Define to 1 if you have the `grantpt' function. */
+#undef HAVE_GRANTPT
+
+/* Define to 1 if you have the <inttypes.h> header file. */
+#undef HAVE_INTTYPES_H
+
+/* Define to 1 if you have the `socket' library (-lsocket). */
+#undef HAVE_LIBSOCKET
+
+/* Define to 1 if you have the `util' library (-lutil). */
+#undef HAVE_LIBUTIL
+
+/* Define to 1 if you have the <libutil.h> header file. */
+#undef HAVE_LIBUTIL_H
+
+/* Define to 1 if you have the <memory.h> header file. */
+#undef HAVE_MEMORY_H
+
+/* Define to 1 if you have the `memset' function. */
+#undef HAVE_MEMSET
+
+/* Define to 1 if you have the `openpty' function. */
+#undef HAVE_OPENPTY
+
+/* Define to 1 if you have the `ptsname' function. */
+#undef HAVE_PTSNAME
+
+/* Define to 1 if you have the <pty.h> header file. */
+#undef HAVE_PTY_H
+
+/* Define to 1 if you have the `select' function. */
+#undef HAVE_SELECT
+
+/* Define to 1 if you have the `socket' function. */
+#undef HAVE_SOCKET
+
+/* Define to 1 if you have the <stdint.h> header file. */
+#undef HAVE_STDINT_H
+
+/* Define to 1 if you have the <stdlib.h> header file. */
+#undef HAVE_STDLIB_H
+
+/* Define to 1 if you have the `strerror' function. */
+#undef HAVE_STRERROR
+
+/* Define to 1 if you have the <strings.h> header file. */
+#undef HAVE_STRINGS_H
+
+/* Define to 1 if you have the <string.h> header file. */
+#undef HAVE_STRING_H
+
+/* Define to 1 if you have the <stropts.h> header file. */
+#undef HAVE_STROPTS_H
+
+/* Define to 1 if you have the <sys/ioctl.h> header file. */
+#undef HAVE_SYS_IOCTL_H
+
+/* Define to 1 if you have the <sys/resource.h> header file. */
+#undef HAVE_SYS_RESOURCE_H
+
+/* Define to 1 if you have the <sys/select.h> header file. */
+#undef HAVE_SYS_SELECT_H
+
+/* Define to 1 if you have the <sys/socket.h> header file. */
+#undef HAVE_SYS_SOCKET_H
+
+/* Define to 1 if you have the <sys/stat.h> header file. */
+#undef HAVE_SYS_STAT_H
+
+/* Define to 1 if you have the <sys/time.h> header file. */
+#undef HAVE_SYS_TIME_H
+
+/* Define to 1 if you have the <sys/types.h> header file. */
+#undef HAVE_SYS_TYPES_H
+
+/* Define to 1 if you have the <termios.h> header file. */
+#undef HAVE_TERMIOS_H
+
+/* Define to 1 if you have the <unistd.h> header file. */
+#undef HAVE_UNISTD_H
+
+/* Define to 1 if you have the `unlockpt' function. */
+#undef HAVE_UNLOCKPT
+
+/* Define to 1 if you have the <util.h> header file. */
+#undef HAVE_UTIL_H
+
+/* Define to the address where bug reports for this package should be sent. */
+#undef PACKAGE_BUGREPORT
+
+/* Define to the full name of this package. */
+#undef PACKAGE_NAME
+
+/* Define to the full name and version of this package. */
+#undef PACKAGE_STRING
+
+/* Define to the one symbol short name of this package. */
+#undef PACKAGE_TARNAME
+
+/* Define to the home page for this package. */
+#undef PACKAGE_URL
+
+/* Define to the version of this package. */
+#undef PACKAGE_VERSION
+
+/* Define as the return type of signal handlers (`int' or `void'). */
+#undef RETSIGTYPE
+
+/* Define to 1 if you have the ANSI C header files. */
+#undef STDC_HEADERS
+
+/* Define to 1 if you can safely include both <sys/time.h> and <time.h>. */
+#undef TIME_WITH_SYS_TIME
+
+/* Define to empty if `const' does not conform to ANSI C. */
+#undef const
+
+/* Define to `int' if <sys/types.h> does not define. */
+#undef pid_t
+
+/* Define to `int' if <sys/types.h> does not define. */
+#undef ssize_t

src/dtach-0.9/configure.ac

@@ -0,0 +1,37 @@
+# Process this file with autoconf to produce a configure script.
+AC_INIT(dtach, 0.9, crigler@users.sourceforge.net)
+AC_PREREQ(2.60)
+AC_CONFIG_SRCDIR(main.c)
+AC_CONFIG_HEADER(config.h)
+
+# Checks for programs.
+AC_PROG_CC
+AC_PROG_GCC_TRADITIONAL
+
+if test "$GCC" = yes; then
+	CFLAGS="$CFLAGS -W -Wall";
+fi
+
+# Checks for libraries.
+AC_CHECK_LIB(util, openpty)
+AC_CHECK_LIB(socket, socket)
+
+# Checks for header files.
+AC_CHECK_HEADERS(fcntl.h sys/select.h sys/socket.h sys/time.h)
+AC_CHECK_HEADERS(sys/ioctl.h sys/resource.h pty.h termios.h util.h)
+AC_CHECK_HEADERS(libutil.h stropts.h)
+AC_HEADER_TIME
+
+# Checks for typedefs, structures, and compiler characteristics.
+AC_C_CONST
+AC_TYPE_PID_T
+AC_TYPE_SSIZE_T
+
+# Checks for library functions.
+AC_TYPE_SIGNAL
+AC_CHECK_FUNCS(atexit dup2 memset)
+AC_CHECK_FUNCS(select socket strerror)
+AC_CHECK_FUNCS(openpty forkpty ptsname grantpt unlockpt)
+
+AC_CONFIG_FILES(Makefile)
+AC_OUTPUT

src/dtach-0.9/dtach.1

@@ -0,0 +1,216 @@
+.TH dtach 1 "May 2016" "dtach 0.9"
+.SH NAME
+dtach \- simple program that emulates the detach feature of screen.
+.SH SYNOPSIS
+.B dtach \-a
+.I <socket> <options>
+.br
+.B dtach \-A
+.I <socket> <options> <command...>
+.br
+.B dtach \-c
+.I <socket> <options> <command...>
+.br
+.B dtach \-n
+.I <socket> <options> <command...>
+.br
+.B dtach \-N
+.I <socket> <options> <command...>
+.br
+.B dtach \-p
+.I <socket>
+
+.SH DESCRIPTION
+.B dtach
+is a program that emulates the detach feature of screen. It is designed
+to be transparent and un-intrusive; it avoids interpreting the input and output
+between attached terminals and the program under its control. Consequently, it
+works best with full-screen applications such as emacs.
+
+.B dtach
+is intended for users who want the detach feature of screen without the other
+overhead of screen. It is tiny, does not use many libraries, and stays
+out of the way as much as possible.
+
+.SS SESSIONS
+A session in
+.B dtach
+is a single instance in which a program is running under the control of
+.BR dtach .
+The program is disassociated from the original terminal, and is thus protected
+from your original terminal being disconnected for some reason.
+.PP
+
+Other instances of 
+.B dtach
+can attach themselves to a particular session. Input and output is copied
+between the program running in the
+.B dtach
+session, and the attached terminals.
+.PP
+
+.B dtach
+avoids interpreting the communication stream between the program and the
+attached terminals; it instead relies on the ability of the attached terminals
+to manage the screen.
+.PP
+
+Sessions are represented by Unix-domain sockets in the filesystem. No other
+permission checking other than the filesystem access checks is performed.
+.B dtach
+creates a master process that monitors the session socket, the program, and any
+attached terminals.
+
+.PP
+.SS MODES
+.B dtach
+has several modes of operation. It can create a new session in which a
+program is executed, or it can attach to an existing session. The first
+argument specifies which mode
+.B dtach
+should operate in.
+.TP
+.B \-a
+Attach to an existing session.
+.B dtach
+attaches itself to the session specified by
+.IR <socket> .
+After the attach is completed, the window size of the current terminal is sent
+to the master process, and a redraw is also requested. 
+.TP
+.B \-A
+Attach to an existing session, or create a new one.
+.B dtach
+first tries to attach to the session specified by
+.I <socket>
+if possible. If the attempt to open the socket fails,
+.B dtach
+tries to create a new session before attaching to it.
+.TP
+.B \-c
+Creates a new session. A new session is created in which the specified program
+is executed.
+.B dtach
+then tries to attach itself to the newly created session.
+.TP
+.B \-n
+Creates a new session, without attaching to it. A new session is created in
+which the specified program is executed.
+.B dtach
+does not try to attach to the newly created session, however, and exits
+instead.
+.TP
+.B \-N
+Creates a new session, without attaching to it or daemonizing. A new session is
+created in which the specified program is executed.
+.B dtach
+does not try to attach to the newly created session, however, and will stay
+in the foreground until the program exits.
+.TP
+.B \-p
+Copies the contents of standard input to a session.
+.B dtach
+connects to the session specified by
+.IR <socket> ,
+copies the contents of standard input to the session, and then exits. dtach
+will not scan the input for a detach character.
+
+.PP
+.SS OPTIONS
+.B dtach
+has a few options that allow you to modify its behavior. Each attaching
+process can have separate settings for these options, which allows for
+some flexibility.
+
+.TP
+.BI "\-e " "<char>"
+Sets the detach character to
+.IR <char> .
+When the detach character is pressed,
+.B dtach
+detaches itself from the current session and exits. The process running in
+the session is unaffected by the detach. By default, the detach character is
+set to ^\e (Ctrl-\e).
+
+.TP
+.B \-E
+Disables the detach character.
+.B dtach
+does not try to scan input from the terminal for a detach character. The only
+way to detach from the session is then by sending the attaching process an
+appropriate signal.
+
+.TP
+.BI "\-r " "<method>"
+Sets the redraw method to
+.IR <method> .
+The valid methods are
+.IR none ,
+.IR ctrl_l ,
+or
+.IR winch .
+
+.I none
+disables redrawing completely,
+.I ctrl_l
+sends a Ctrl L character to the program if the terminal is in
+character-at-a-time and no-echo mode, and
+.I winch
+forces a WINCH signal to be sent to the program.
+
+When creating a new session, the specified method is used as the default
+redraw method for the session. If not specified, the
+.I ctrl_l
+method is used.
+
+.TP
+.B \-z
+Disables processing of the suspend key.
+Normally,
+.B dtach
+will suspend itself when the suspend key is pressed. With this option, the
+suspend character is sent to the session instead of being handled by
+.BR dtach .
+
+.PP
+.SH EXAMPLES
+
+The following example creates a new session that has the detach character
+and suspend processing disabled. A socket is created in the /tmp directory
+for the session.
+
+.nf
+   $ dtach \-c /tmp/foozle \-Ez bash
+.fi
+
+The following example attaches to the /tmp/foozle session if it exists, and if
+not, creates a new session using /tmp/foozle as the socket for the session.
+Processing of the suspend character is also disabled for the attach instance.
+
+.nf
+   $ dtach \-A /tmp/foozle \-z bash
+.fi
+
+The following example attaches to the /tmp/foozle session, using the
+.I winch
+redraw method to redraw the screen.
+
+.nf
+   $ dtach \-a /tmp/foozle \-r winch
+.fi
+
+The following example creates a new session and sets the default redraw method
+for the session to the
+.I winch
+redraw method.
+
+.nf
+   $ dtach \-c /tmp/foozle \-r winch bash
+.fi
+
+.PP
+.SH AUTHOR
+Ned T. Crigler <crigler@users.sourceforge.net>.
+
+.SH "SEE ALSO"
+.BR screen "(1)"

src/dtach-0.9/dtach.h

@@ -0,0 +1,137 @@
+/*
+    dtach - A simple program that emulates the detach feature of screen.
+    Copyright (C) 2001, 2004-2016 Ned T. Crigler
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+#ifndef dtach_h
+#define dtach_h
+
+#include <config.h>
+
+#include <errno.h>
+#include <fcntl.h>
+#include <signal.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if TIME_WITH_SYS_TIME
+#include <sys/time.h>
+#include <time.h>
+#else
+#if HAVE_SYS_TIME_H
+#include <sys/time.h>
+#else
+#include <time.h>
+#endif
+#endif
+
+#ifdef HAVE_PTY_H
+#include <pty.h>
+#endif
+
+#ifdef HAVE_UTIL_H
+#include <util.h>
+#endif
+
+#ifdef HAVE_LIBUTIL_H
+#include <libutil.h>
+#endif
+
+#ifdef HAVE_STROPTS_H
+#include <stropts.h>
+#endif
+
+#ifdef HAVE_UNISTD_H
+#include <unistd.h>
+#endif
+
+#ifdef HAVE_SYS_IOCTL_H
+#include <sys/ioctl.h>
+#endif
+
+#ifdef HAVE_SYS_RESOURCE_H
+#include <sys/resource.h>
+#endif
+
+#include <termios.h>
+#include <sys/select.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+
+#ifndef S_ISREG
+#define S_ISREG(m) (((m) & S_IFMT) == S_IFREG)
+#endif
+
+#ifndef S_ISSOCK
+#define S_ISSOCK(m) (((m) & S_IFMT) == S_IFSOCK)
+#endif
+
+extern char *progname, *sockname;
+extern int detach_char, no_suspend, redraw_method;
+extern struct termios orig_term;
+extern int dont_have_tty;
+
+enum
+{
+	MSG_PUSH	= 0,
+	MSG_ATTACH	= 1,
+	MSG_DETACH	= 2,
+	MSG_WINCH	= 3,
+	MSG_REDRAW	= 4,
+};
+
+enum
+{
+	REDRAW_UNSPEC	= 0,
+	REDRAW_NONE	= 1,
+	REDRAW_CTRL_L	= 2,
+	REDRAW_WINCH	= 3,
+};
+
+/* The client to master protocol. */
+struct packet
+{
+	unsigned char type;
+	unsigned char len;
+	union
+	{
+		unsigned char buf[sizeof(struct winsize)];
+		struct winsize ws;
+	} u;
+};
+
+/*
+** The master sends a simple stream of text to the attaching clients, without
+** any protocol. This might change back to the packet based protocol in the
+** future. In the meantime, however, we minimize the amount of data sent back
+** and forth between the client and the master. BUFSIZE is the size of the
+** buffer used for the text stream.
+*/
+#define BUFSIZE 4096
+
+/* This hopefully moves to the bottom of the screen */
+#define EOS "\033[999H"
+
+int attach_main(int noerror);
+int master_main(char **argv, int waitattach, int dontfork);
+int push_main(void);
+
+#ifdef sun
+#define BROKEN_MASTER
+#endif
+#endif

src/dtach-0.9/dtach.spec

@@ -0,0 +1,108 @@
+Summary: A simple program that emulates the detach feature of screen.
+Name: dtach
+Version: 0.9
+Release: 1
+License: GPL
+URL: http://dtach.sourceforge.net
+Group: Applications/System
+Source: http://prdownloads.sourceforge.net/dtach/dtach-%{version}.tar.gz
+Buildroot: %{_tmppath}/%{name}-%{version}-root
+ 
+%description
+
+dtach is a program that emulates the detach feature of screen, with
+less overhead.  It is designed to be transparent and un-intrusive; it
+avoids interpreting the input and output between attached terminals
+and the program under its control. Consequently, it works best with
+full-screen applications such as emacs.
+  
+%prep
+%setup
+ 
+%build
+%configure
+make
+ 
+%install
+rm -rf $RPM_BUILD_ROOT/*
+mkdir -p $RPM_BUILD_ROOT/%{_bindir}
+mkdir -p $RPM_BUILD_ROOT/usr/share/doc/dtach-%{version}
+mkdir -p $RPM_BUILD_ROOT/%{_mandir}/man1
+install -m 755 dtach $RPM_BUILD_ROOT/%{_bindir}/dtach
+install -m 644 dtach.1 $RPM_BUILD_ROOT/%{_mandir}/man1/dtach.1
+
+%clean
+make clean
+rm -rf $RPM_BUILD_ROOT
+rm -rf $RPM_BUILD_DIR/%{name}-%{version}
+
+%files
+%defattr(-,root,root,-)
+%doc COPYING README
+%{_bindir}/dtach
+%{_mandir}/*/*
+
+%changelog
+* Sun May 8 2016 Ned T. Crigler <crigler@users.sourceforge.net> 0.9
+- New release
+
+* Wed Jan 30 2008 Ned T. Crigler <crigler@users.sourceforge.net> 0.8
+- New release
+
+* Sat Jul 3 2004 Ned T. Crigler <crigler@users.sourceforge.net> 0.7
+- New release
+
+* Fri Nov 30 2001 Ned T. Crigler <crigler@hell-city.org> 0.5
+- Fix fd leakage.
+- Prevent atexit from being called twice on dtach -A.
+
+* Fri Nov 30 2001 Trond Eivind Glomsrød <teg@redhat.com> 0.4-1
+- s/Copyright/License/
+- Minor description change
+- fix use of %%doc
+- Add full location of source tarball
+
+* Sat Nov 03 2001 Ned T. Crigler <crigler@hell-city.org> 0.4
+- Portability updates thanks to sourceforge's compile farm. dtach should now
+  work on: FreeBSD, Debian/alpha, Debian/PPC, Debian/sparc, Debian/PPC, and
+  Solaris.
+
+* Thu Sep 27 2001 Ned T. Crigler <crigler@hell-city.org>
+- Modified spec file URL: to point to http://dtach.sourceforge.net
+
+* Wed Sep 26 2001 Ned T. Crigler <crigler@hell-city.org> 0.3
+- Use getrlimit and dynamically allocate the data structures, if possible.
+- Added some more autoconf checks.
+- Initial sourceforge release.
+
+* Thu Sep 20 2001 Ned T. Crigler <crigler@hell-city.org>
+- Changed the master to send a stream of text to attaching clients instead
+  of sending a huge packet all the time.
+- Decreased the client <-> master packet size.
+- Changed the attach code so that it tells the master when a suspend occurs.
+
+* Tue Sep 18 2001 Ned T. Crigler <crigler@hell-city.org>
+- Fixed a typo in dtach.1
+
+* Tue Sep 18 2001 Ned T. Crigler <crigler@hell-city.org> 0.2
+- Removed silly thinko regarding terminal settings in attach, we
+  always set the terminal to raw mode now.
+- Moved redraw code into the master, which tries to be smarter when
+  using ^L.
+- Moved the code that obtains the current terminal settings into main,
+  preventing a race condition between the master and attach processes.
+- Rewrote argument parsing code.
+- Changed name to dtach.
+- Added a man page.
+
+* Mon Sep 17 2001 Ned T. Crigler <crigler@hell-city.org>
+- Changed fchmod to chmod in create_socket.
+
+* Mon Sep 17 2001 Isaiah Weiner <iweiner@redhat.com>
+- Modified spec file to correct detach binary permissions
+- Modified spec file to correct detach documentation path
+- Modified spec file URL: to point to http://people.redhat.com/iweiner/detach
+- Modified spec file %clean to remove buildroot and builddir.
+
+* Mon Sep 17 2001 Ned T. Crigler <crigler@hell-city.org> 0.1
+- Initial rpm release.

src/dtach-0.9/main.c

@@ -0,0 +1,284 @@
+/*
+    dtach - A simple program that emulates the detach feature of screen.
+    Copyright (C) 2004-2016 Ned T. Crigler
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+#include "dtach.h"
+
+/*
+** dtach is a quick hack, since I wanted the detach feature of screen without
+** all the other crud. It'll work best with full-screen applications, as it
+** does not keep track of the screen or anything like that.
+*/
+
+/* Make sure the binary has a copyright. */
+const char copyright[] = "dtach - version " PACKAGE_VERSION "(C)Copyright 2004-2016 Ned T. Crigler";
+
+/* argv[0] from the program */
+char *progname;
+/* The name of the passed in socket. */
+char *sockname;
+/* The character used for detaching. Defaults to '^\' */
+int detach_char = '\\' - 64;
+/* 1 if we should not interpret the suspend character. */
+int no_suspend;
+/* The default redraw method. Initially set to unspecified. */
+int redraw_method = REDRAW_UNSPEC;
+
+/*
+** The original terminal settings. Shared between the master and attach
+** processes. The master uses it to initialize the pty, and the attacher uses
+** it to restore the original settings.
+*/
+struct termios orig_term;
+int dont_have_tty;
+
+static void
+usage()
+{
+	printf(
+		"dtach - version %s, compiled on %s at %s.\n"
+		"Usage: dtach -a <socket> <options>\n"
+		"       dtach -A <socket> <options> <command...>\n"
+		"       dtach -c <socket> <options> <command...>\n"
+		"       dtach -n <socket> <options> <command...>\n"
+		"       dtach -N <socket> <options> <command...>\n"
+		"       dtach -p <socket>\n"
+		"Modes:\n"
+		"  -a\t\tAttach to the specified socket.\n"
+		"  -A\t\tAttach to the specified socket, or create it if it\n"
+		"\t\t  does not exist, running the specified command.\n"
+		"  -c\t\tCreate a new socket and run the specified command.\n"
+		"  -n\t\tCreate a new socket and run the specified command "
+		"detached.\n"
+		"  -N\t\tCreate a new socket and run the specified command "
+		"detached,\n"
+		"\t\t  and have dtach run in the foreground.\n"
+		"  -p\t\tCopy the contents of standard input to the specified\n"
+		"\t\t  socket.\n"
+		"Options:\n"
+		"  -e <char>\tSet the detach character to <char>, defaults "
+		"to ^\\.\n"
+		"  -E\t\tDisable the detach character.\n"
+		"  -r <method>\tSet the redraw method to <method>. The "
+		"valid methods are:\n"
+		"\t\t     none: Don't redraw at all.\n"
+		"\t\t   ctrl_l: Send a Ctrl L character to the program.\n"
+		"\t\t    winch: Send a WINCH signal to the program.\n"
+		"  -z\t\tDisable processing of the suspend key.\n"
+		"\nReport any bugs to <" PACKAGE_BUGREPORT ">.\n",
+		PACKAGE_VERSION, __DATE__, __TIME__);
+	exit(0);
+}
+
+int
+main(int argc, char **argv)
+{
+	int mode = 0;
+
+	/* Save the program name */
+	progname = argv[0];
+	++argv; --argc;
+
+	/* Parse the arguments */
+	if (argc >= 1 && **argv == '-')
+	{
+		if (strncmp(*argv, "--help", strlen(*argv)) == 0)
+			usage();
+		else if (strncmp(*argv, "--version", strlen(*argv)) == 0)
+		{
+			printf("dtach - version %s, compiled on %s at %s.\n",
+				PACKAGE_VERSION, __DATE__, __TIME__);
+			return 0;
+		}
+
+		mode = argv[0][1];
+		if (mode == '?')
+			usage();
+		else if (mode != 'a' && mode != 'c' && mode != 'n' &&
+			 mode != 'A' && mode != 'N' && mode != 'p')
+		{
+			printf("%s: Invalid mode '-%c'\n", progname, mode);
+			printf("Try '%s --help' for more information.\n",
+				progname);
+			return 1;
+		}
+	}
+	if (!mode)
+	{
+		printf("%s: No mode was specified.\n", progname);
+		printf("Try '%s --help' for more information.\n",
+			progname);
+		return 1;
+	}
+	++argv; --argc;
+
+	if (argc < 1)
+	{
+		printf("%s: No socket was specified.\n", progname);
+		printf("Try '%s --help' for more information.\n",
+			progname);
+		return 1;
+	}
+	sockname = *argv;
+	++argv; --argc;
+
+	if (mode == 'p')
+	{
+		if (argc > 0)
+		{
+			printf("%s: Invalid number of arguments.\n",
+				progname);
+			printf("Try '%s --help' for more information.\n",
+				progname);
+			return 1;
+		}
+		return push_main();
+	}
+
+	while (argc >= 1 && **argv == '-')
+	{
+		char *p;
+
+		for (p = argv[0] + 1; *p; ++p)
+		{
+			if (*p == 'E')
+				detach_char = -1;
+			else if (*p == 'z')
+				no_suspend = 1;
+			else if (*p == 'e')
+			{
+				++argv; --argc;
+				if (argc < 1)
+				{
+					printf("%s: No escape character "
+						"specified.\n", progname);	
+					printf("Try '%s --help' for more "
+						"information.\n", progname);
+					return 1;
+				}
+				if (argv[0][0] == '^' && argv[0][1])
+				{
+					if (argv[0][1] == '?')
+						detach_char = '\177';
+					else
+						detach_char = argv[0][1] & 037;
+				}
+				else
+					detach_char = argv[0][0];
+				break;
+			}
+			else if (*p == 'r')
+			{
+				++argv; --argc;
+				if (argc < 1)
+				{
+					printf("%s: No redraw method "
+						"specified.\n", progname);	
+					printf("Try '%s --help' for more "
+						"information.\n", progname);
+					return 1;
+				}
+				if (strcmp(argv[0], "none") == 0)
+					redraw_method = REDRAW_NONE;
+				else if (strcmp(argv[0], "ctrl_l") == 0)
+					redraw_method = REDRAW_CTRL_L;
+				else if (strcmp(argv[0], "winch") == 0)
+					redraw_method = REDRAW_WINCH;
+				else
+				{
+					printf("%s: Invalid redraw method "
+						"specified.\n", progname);	
+					printf("Try '%s --help' for more "
+						"information.\n", progname);
+					return 1;
+				}
+				break;
+			}
+			else
+			{
+				printf("%s: Invalid option '-%c'\n",
+					progname, *p);
+				printf("Try '%s --help' for more information.\n",
+					progname);
+				return 1;
+			}
+		}
+		++argv; --argc;
+	}
+
+	if (mode != 'a' && argc < 1)
+	{
+		printf("%s: No command was specified.\n", progname);
+		printf("Try '%s --help' for more information.\n",
+			progname);
+		return 1;
+	}
+
+	/* Save the original terminal settings. */
+	if (tcgetattr(0, &orig_term) < 0)
+	{
+		memset(&orig_term, 0, sizeof(struct termios));
+		dont_have_tty = 1;
+	}
+
+	if (dont_have_tty && mode != 'n' && mode != 'N')
+	{
+		printf("%s: Attaching to a session requires a terminal.\n",
+			progname);
+		return 1;
+	}
+
+	if (mode == 'a')
+	{
+		if (argc > 0)
+		{
+			printf("%s: Invalid number of arguments.\n",
+				progname);
+			printf("Try '%s --help' for more information.\n",
+				progname);
+			return 1;
+		}
+		return attach_main(0);
+	}
+	else if (mode == 'n')
+		return master_main(argv, 0, 0);
+	else if (mode == 'N')
+		return master_main(argv, 0, 1);
+	else if (mode == 'c')
+	{
+		if (master_main(argv, 1, 0) != 0)
+			return 1;
+		return attach_main(0);
+	}
+	else if (mode == 'A')
+	{
+		/* Try to attach first. If that doesn't work, create a new
+		** socket. */
+		if (attach_main(1) != 0)
+		{
+			if (errno == ECONNREFUSED || errno == ENOENT)
+			{
+				if (errno == ECONNREFUSED)
+					unlink(sockname);
+				if (master_main(argv, 1, 0) != 0)
+					return 1;
+			}
+			return attach_main(0);
+		}
+	}
+	return 0;
+}

src/dtach-0.9/master.c

@@ -0,0 +1,800 @@
+/*
+    dtach - A simple program that emulates the detach feature of screen.
+    Copyright (C) 2004-2016 Ned T. Crigler
+
+    This program is free software; you can redistribute it and/or modify
+    it under the terms of the GNU General Public License as published by
+    the Free Software Foundation; either version 2 of the License, or
+    (at your option) any later version.
+
+    This program 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
+    along with this program; if not, write to the Free Software
+    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
+*/
+#include "dtach.h"
+
+/* The pty struct - The pty information is stored here. */
+struct pty
+{
+	/* File descriptor of the pty */
+	int fd;
+#ifdef BROKEN_MASTER
+	/* File descriptor of the slave side of the pty. For broken systems. */
+	int slave;
+#endif
+	/* Process id of the child. */
+	pid_t pid;
+	/* The terminal parameters of the pty. Old and new for comparision
+	** purposes. */
+	struct termios term;
+	/* The current window size of the pty. */
+	struct winsize ws;
+};
+
+/* A connected client */
+struct client
+{
+	/* The next client in the linked list. */
+	struct client *next;
+	/* The previous client in the linked list. */
+	struct client **pprev;
+	/* File descriptor of the client. */
+	int fd;
+	/* Whether or not the client is attached. */
+	int attached;
+};
+
+/* The list of connected clients. */
+static struct client *clients;
+/* The pseudo-terminal created for the child process. */
+static struct pty the_pty;
+
+#ifndef HAVE_FORKPTY
+pid_t forkpty(int *amaster, char *name, struct termios *termp,
+	struct winsize *winp);
+#endif
+
+/* Unlink the socket */
+static void
+unlink_socket(void)
+{
+	unlink(sockname);
+}
+
+/* Signal */
+static RETSIGTYPE 
+die(int sig)
+{
+	/* Well, the child died. */
+	if (sig == SIGCHLD)
+	{
+#ifdef BROKEN_MASTER
+		/* Damn you Solaris! */
+		close(the_pty.fd);
+#endif
+		return;
+	}
+	exit(1);
+}
+
+/* Sets a file descriptor to non-blocking mode. */
+static int
+setnonblocking(int fd)
+{
+	int flags;
+
+#if defined(O_NONBLOCK)
+	flags = fcntl(fd, F_GETFL);
+	if (flags < 0 || fcntl(fd, F_SETFL, flags | O_NONBLOCK) < 0)
+		return -1;
+	return 0;
+#elif defined(FIONBIO)
+	flags = 1;
+	if (ioctl(fd, FIONBIO, &flags) < 0)
+		return -1;
+	return 0;
+#else
+#warning Do not know how to set non-blocking mode.
+	return 0;
+#endif
+}
+
+/* Initialize the pty structure. */
+static int
+init_pty(char **argv, int statusfd)
+{
+	/* Use the original terminal's settings. We don't have to set the
+	** window size here, because the attacher will send it in a packet. */
+	the_pty.term = orig_term;
+	memset(&the_pty.ws, 0, sizeof(struct winsize));
+
+	/* Create the pty process */
+	if (!dont_have_tty)
+		the_pty.pid = forkpty(&the_pty.fd, NULL, &the_pty.term, NULL);
+	else
+		the_pty.pid = forkpty(&the_pty.fd, NULL, NULL, NULL);
+	if (the_pty.pid < 0)
+		return -1;
+	else if (the_pty.pid == 0)
+	{
+		/* Child.. Execute the program. */
+		execvp(*argv, argv);
+
+		/* Report the error to statusfd if we can, or stdout if we
+		** can't. */
+		if (statusfd != -1)
+			dup2(statusfd, 1);
+		else
+			printf(EOS "\r\n");
+
+		printf("%s: could not execute %s: %s\r\n", progname,
+		       *argv, strerror(errno));
+		fflush(stdout);
+		_exit(127);
+	}
+	/* Parent.. Finish up and return */
+#ifdef BROKEN_MASTER
+	{
+		char *buf;
+
+		buf = ptsname(the_pty.fd);
+		the_pty.slave = open(buf, O_RDWR|O_NOCTTY);
+	}
+#endif
+	return 0;
+}
+
+/* Send a signal to the slave side of a pseudo-terminal. */
+static void
+killpty(struct pty *pty, int sig)
+{
+	pid_t pgrp = -1;
+
+#ifdef TIOCSIGNAL
+	if (ioctl(pty->fd, TIOCSIGNAL, sig) >= 0)
+		return;
+#endif
+#ifdef TIOCSIG
+	if (ioctl(pty->fd, TIOCSIG, sig) >= 0)
+		return;
+#endif
+#ifdef TIOCGPGRP
+#ifdef BROKEN_MASTER
+	if (ioctl(pty->slave, TIOCGPGRP, &pgrp) >= 0 && pgrp != -1 &&
+		kill(-pgrp, sig) >= 0)
+		return;
+#endif
+	if (ioctl(pty->fd, TIOCGPGRP, &pgrp) >= 0 && pgrp != -1 &&
+		kill(-pgrp, sig) >= 0)
+		return;
+#endif
+
+	/* Fallback using the child's pid. */
+	kill(-pty->pid, sig);
+}
+
+/* Creates a new unix domain socket. */
+static int
+create_socket(char *name)
+{
+	int s;
+	struct sockaddr_un sockun;
+
+	if (strlen(name) > sizeof(sockun.sun_path) - 1)
+	{
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+
+	s = socket(PF_UNIX, SOCK_STREAM, 0);
+	if (s < 0)
+		return -1;
+	sockun.sun_family = AF_UNIX;
+	strcpy(sockun.sun_path, name);
+	if (bind(s, (struct sockaddr*)&sockun, sizeof(sockun)) < 0)
+	{
+		close(s);
+		return -1;
+	}
+	if (listen(s, 128) < 0)
+	{
+		close(s);
+		return -1;
+	}
+	if (setnonblocking(s) < 0)
+	{
+		close(s);
+		return -1;
+	}
+	/* chmod it to prevent any suprises */
+	if (chmod(name, 0600) < 0)
+	{
+		close(s);
+		return -1;
+	}
+	return s;
+}
+
+/* Update the modes on the socket. */
+static void
+update_socket_modes(int exec)
+{
+	struct stat st;
+	mode_t newmode;
+
+	if (stat(sockname, &st) < 0)
+		return;
+
+	if (exec)
+		newmode = st.st_mode | S_IXUSR;
+	else
+		newmode = st.st_mode & ~S_IXUSR;
+
+	if (st.st_mode != newmode)
+		chmod(sockname, newmode);
+}
+
+/* Process activity on the pty - Input and terminal changes are sent out to
+** the attached clients. If the pty goes away, we die. */
+static void
+pty_activity(int s)
+{
+	unsigned char buf[BUFSIZE];
+	ssize_t len;
+	struct client *p;
+	fd_set readfds, writefds;
+	int highest_fd, nclients;
+
+	/* Read the pty activity */
+	len = read(the_pty.fd, buf, sizeof(buf));
+
+	/* Error -> die */
+	if (len <= 0)
+		exit(1);
+
+#ifdef BROKEN_MASTER
+	/* Get the current terminal settings. */
+	if (tcgetattr(the_pty.slave, &the_pty.term) < 0)
+		exit(1);
+#else
+	/* Get the current terminal settings. */
+	if (tcgetattr(the_pty.fd, &the_pty.term) < 0)
+		exit(1);
+#endif
+
+top:
+	/*
+	** Wait until at least one client is writable. Also wait on the control
+	** socket in case a new client tries to connect.
+	*/
+	FD_ZERO(&readfds);
+	FD_ZERO(&writefds);
+	FD_SET(s, &readfds);
+	highest_fd = s;
+	for (p = clients, nclients = 0; p; p = p->next)
+	{
+		if (!p->attached)
+			continue;
+		FD_SET(p->fd, &writefds);
+		if (p->fd > highest_fd)
+			highest_fd = p->fd;
+		nclients++;
+	}
+	if (nclients == 0)
+		return;
+	if (select(highest_fd + 1, &readfds, &writefds, NULL, NULL) < 0)
+		return;
+
+	/* Send the data out to the clients. */
+	for (p = clients, nclients = 0; p; p = p->next)
+	{
+		ssize_t written;
+
+		if (!FD_ISSET(p->fd, &writefds))
+			continue;
+
+		written = 0;
+		while (written < len)
+		{
+			ssize_t n = write(p->fd, buf + written, len - written);
+
+			if (n > 0)
+			{
+				written += n;
+				continue;
+			}
+			else if (n < 0 && errno == EINTR)
+				continue;
+			else if (n < 0 && errno != EAGAIN)
+				nclients = -1;
+			break;
+		}
+		if (nclients != -1 && written == len)
+			nclients++;
+	}
+
+	/* Try again if nothing happened. */
+	if (!FD_ISSET(s, &readfds) && nclients == 0)
+		goto top;
+}
+
+/* Process activity on the control socket */
+static void
+control_activity(int s)
+{
+	int fd;
+	struct client *p;
+ 
+	/* Accept the new client and link it in. */
+	fd = accept(s, NULL, NULL);
+	if (fd < 0)
+		return;
+	else if (setnonblocking(fd) < 0)
+	{
+		close(fd);
+		return;
+	}
+
+	/* Link it in. */
+	p = malloc(sizeof(struct client));
+	p->fd = fd;
+	p->attached = 0;
+	p->pprev = &clients;
+	p->next = *(p->pprev);
+	if (p->next)
+		p->next->pprev = &p->next;
+	*(p->pprev) = p;
+}
+
+/* Process activity from a client. */
+static void
+client_activity(struct client *p)
+{
+	ssize_t len;
+	struct packet pkt;
+
+	/* Read the activity. */
+	len = read(p->fd, &pkt, sizeof(struct packet));
+	if (len < 0 && (errno == EAGAIN || errno == EINTR))
+		return;
+
+	/* Close the client on an error. */
+	if (len <= 0)
+	{
+		close(p->fd);
+		if (p->next)
+			p->next->pprev = p->pprev;
+		*(p->pprev) = p->next;
+		free(p);
+		return;
+	} 
+
+	/* Push out data to the program. */
+	if (pkt.type == MSG_PUSH)
+	{
+		if (pkt.len <= sizeof(pkt.u.buf))
+			write(the_pty.fd, pkt.u.buf, pkt.len);
+	}
+
+	/* Attach or detach from the program. */
+	else if (pkt.type == MSG_ATTACH)
+		p->attached = 1;
+	else if (pkt.type == MSG_DETACH)
+		p->attached = 0;
+
+	/* Window size change request, without a forced redraw. */
+	else if (pkt.type == MSG_WINCH)
+	{
+		the_pty.ws = pkt.u.ws;
+		ioctl(the_pty.fd, TIOCSWINSZ, &the_pty.ws);
+	}
+
+	/* Force a redraw using a particular method. */
+	else if (pkt.type == MSG_REDRAW)
+	{
+		int method = pkt.len;
+
+		/* If the client didn't specify a particular method, use
+		** whatever we had on startup. */
+		if (method == REDRAW_UNSPEC)
+			method = redraw_method;
+		if (method == REDRAW_NONE)
+			return;
+
+		/* Set the window size. */
+		the_pty.ws = pkt.u.ws;
+		ioctl(the_pty.fd, TIOCSWINSZ, &the_pty.ws);
+
+		/* Send a ^L character if the terminal is in no-echo and
+		** character-at-a-time mode. */
+		if (method == REDRAW_CTRL_L)
+		{
+			char c = '\f';
+
+                	if (((the_pty.term.c_lflag & (ECHO|ICANON)) == 0) &&
+                        	(the_pty.term.c_cc[VMIN] == 1))
+			{
+				write(the_pty.fd, &c, 1);
+			}
+		}
+		/* Send a WINCH signal to the program. */
+		else if (method == REDRAW_WINCH)
+		{
+			killpty(&the_pty, SIGWINCH);
+		}
+	}
+}
+
+/* The master process - It watches over the pty process and the attached */
+/* clients. */
+static void
+master_process(int s, char **argv, int waitattach, int statusfd)
+{
+	struct client *p, *next;
+	fd_set readfds;
+	int highest_fd;
+	int nullfd;
+
+	int has_attached_client = 0;
+
+	/* Okay, disassociate ourselves from the original terminal, as we
+	** don't care what happens to it. */
+	setsid();
+
+	/* Set a trap to unlink the socket when we die. */
+	atexit(unlink_socket);
+
+	/* Create a pty in which the process is running. */
+	signal(SIGCHLD, die);
+	if (init_pty(argv, statusfd) < 0)
+	{
+		if (statusfd != -1)
+			dup2(statusfd, 1);
+		if (errno == ENOENT)
+			printf("%s: Could not find a pty.\n", progname);
+		else
+			printf("%s: init_pty: %s\n", progname, strerror(errno));
+		exit(1);
+	}
+
+	/* Set up some signals. */
+	signal(SIGPIPE, SIG_IGN);
+	signal(SIGXFSZ, SIG_IGN);
+	signal(SIGHUP, SIG_IGN);
+	signal(SIGTTIN, SIG_IGN);
+	signal(SIGTTOU, SIG_IGN);
+	signal(SIGINT, die);
+	signal(SIGTERM, die);
+
+	/* Close statusfd, since we don't need it anymore. */
+	if (statusfd != -1)
+		close(statusfd);
+
+	/* Make sure stdin/stdout/stderr point to /dev/null. We are now a
+	** daemon. */
+	nullfd = open("/dev/null", O_RDWR);
+	dup2(nullfd, 0);
+	dup2(nullfd, 1);
+	dup2(nullfd, 2);
+	if (nullfd > 2)
+		close(nullfd);
+
+	/* Loop forever. */
+	while (1)
+	{
+		int new_has_attached_client = 0;
+
+		/* Re-initialize the file descriptor set for select. */
+		FD_ZERO(&readfds);
+		FD_SET(s, &readfds);
+		highest_fd = s;
+
+		/*
+		** When waitattach is set, wait until the client attaches
+		** before trying to read from the pty.
+		*/
+		if (waitattach)
+		{
+			if (clients && clients->attached)
+				waitattach = 0;
+		}
+		else
+		{
+			FD_SET(the_pty.fd, &readfds);
+			if (the_pty.fd > highest_fd)
+				highest_fd = the_pty.fd;
+		}
+
+		for (p = clients; p; p = p->next)
+		{
+			FD_SET(p->fd, &readfds);
+			if (p->fd > highest_fd)
+				highest_fd = p->fd;
+
+			if (p->attached)
+				new_has_attached_client = 1;
+		}
+
+		/* chmod the socket if necessary. */
+		if (has_attached_client != new_has_attached_client)
+		{
+			update_socket_modes(new_has_attached_client);
+			has_attached_client = new_has_attached_client;
+		}
+
+		/* Wait for something to happen. */
+		if (select(highest_fd + 1, &readfds, NULL, NULL, NULL) < 0)
+		{
+			if (errno == EINTR || errno == EAGAIN)
+				continue;
+			exit(1);
+		}
+
+		/* New client? */
+		if (FD_ISSET(s, &readfds))
+			control_activity(s);
+		/* Activity on a client? */
+		for (p = clients; p; p = next)
+		{
+			next = p->next;
+			if (FD_ISSET(p->fd, &readfds))
+				client_activity(p);
+		}
+		/* pty activity? */
+		if (FD_ISSET(the_pty.fd, &readfds))
+			pty_activity(s);
+	}
+}
+
+int
+master_main(char **argv, int waitattach, int dontfork)
+{
+	int fd[2] = {-1, -1};
+	int s;
+	pid_t pid;
+
+	/* Use a default redraw method if one hasn't been specified yet. */
+	if (redraw_method == REDRAW_UNSPEC)
+		redraw_method = REDRAW_CTRL_L;
+
+	/* Create the unix domain socket. */
+	s = create_socket(sockname);
+	if (s < 0 && errno == ENAMETOOLONG)
+	{
+		char *slash = strrchr(sockname, '/');
+
+		/* Try to shorten the socket's path name by using chdir. */
+		if (slash)
+		{
+			int dirfd = open(".", O_RDONLY);
+
+			if (dirfd >= 0)
+			{
+				*slash = '\0';
+				if (chdir(sockname) >= 0)
+				{
+					s = create_socket(slash + 1);
+					fchdir(dirfd);
+				}
+				*slash = '/';
+				close(dirfd);
+			}
+		}
+	}
+	if (s < 0)
+	{
+		printf("%s: %s: %s\n", progname, sockname, strerror(errno));
+		return 1;
+	}
+
+#if defined(F_SETFD) && defined(FD_CLOEXEC)
+	fcntl(s, F_SETFD, FD_CLOEXEC);
+
+	/* If FD_CLOEXEC works, create a pipe and use it to report any errors
+	** that occur while trying to execute the program. */
+	if (dontfork)
+	{
+		fd[1] = dup(2);
+		if (fcntl(fd[1], F_SETFD, FD_CLOEXEC) < 0)
+		{
+			close(fd[1]);
+			fd[1] = -1;
+		}
+	}
+	else if (pipe(fd) >= 0)
+	{
+		if (fcntl(fd[0], F_SETFD, FD_CLOEXEC) < 0 ||
+		    fcntl(fd[1], F_SETFD, FD_CLOEXEC) < 0)
+		{
+			close(fd[0]);
+			close(fd[1]);
+			fd[0] = fd[1] = -1;
+		}
+	}
+#endif
+
+	if (dontfork)
+	{
+		master_process(s, argv, waitattach, fd[1]);
+		return 0;
+	}
+
+	/* Fork off so we can daemonize and such */
+	pid = fork();
+	if (pid < 0)
+	{
+		printf("%s: fork: %s\n", progname, strerror(errno));
+		unlink_socket();
+		return 1;
+	}
+	else if (pid == 0)
+	{
+		/* Child - this becomes the master */
+		if (fd[0] != -1)
+			close(fd[0]);
+		master_process(s, argv, waitattach, fd[1]);
+		return 0;
+	}
+	/* Parent - just return. */
+
+#if defined(F_SETFD) && defined(FD_CLOEXEC)
+	/* Check if an error occurred while trying to execute the program. */
+	if (fd[0] != -1)
+	{
+		char buf[1024];
+		ssize_t len;
+
+		close(fd[1]);
+		len = read(fd[0], buf, sizeof(buf));
+		if (len > 0)
+		{
+			write(2, buf, len);
+			kill(pid, SIGTERM);
+			return 1;
+		}
+		close(fd[0]);
+	}
+#endif
+	close(s);
+	return 0;
+}
+
+/* BSDish functions for systems that don't have them. */
+#ifndef HAVE_OPENPTY
+#define HAVE_OPENPTY
+/* openpty: Use /dev/ptmx and Unix98 if we have it. */
+#if defined(HAVE_PTSNAME) && defined(HAVE_GRANTPT) && defined(HAVE_UNLOCKPT)
+int
+openpty(int *amaster, int *aslave, char *name, struct termios *termp,
+	struct winsize *winp)
+{
+	int master, slave;
+	char *buf;
+
+#ifdef _AIX
+	master = open("/dev/ptc", O_RDWR|O_NOCTTY);
+	if (master < 0)
+		return -1;
+	buf = ttyname(master);
+	if (!buf)
+		return -1;
+
+	slave = open(buf, O_RDWR|O_NOCTTY);
+	if (slave < 0)
+		return -1;
+#else
+	master = open("/dev/ptmx", O_RDWR);
+	if (master < 0)
+		return -1;
+	if (grantpt(master) < 0)
+		return -1;
+	if (unlockpt(master) < 0)
+		return -1;
+	buf = ptsname(master);
+	if (!buf)
+		return -1;
+
+	slave = open(buf, O_RDWR|O_NOCTTY);
+	if (slave < 0)
+		return -1;
+
+#ifdef I_PUSH
+	if (ioctl(slave, I_PUSH, "ptem") < 0)
+		return -1;
+	if (ioctl(slave, I_PUSH, "ldterm") < 0)
+		return -1;
+#endif
+#endif
+
+	*amaster = master;
+	*aslave = slave;
+	if (name)
+		strcpy(name, buf);
+	if (termp)
+		tcsetattr(slave, TCSAFLUSH, termp);
+	if (winp)
+		ioctl(slave, TIOCSWINSZ, winp);
+	return 0;
+}
+#else
+#error Do not know how to define openpty.
+#endif
+#endif
+
+#ifndef HAVE_FORKPTY
+#if defined(HAVE_OPENPTY)
+pid_t
+forkpty(int *amaster, char *name, struct termios *termp,
+	struct winsize *winp)
+{
+	pid_t pid;
+	int master, slave;
+
+	if (openpty(&master, &slave, name, termp, winp) < 0)
+		return -1;
+	*amaster = master;
+
+	/* Fork off... */
+	pid = fork();
+	if (pid < 0)
+		return -1;
+	else if (pid == 0)
+	{
+		char *buf;
+		int fd;
+
+		setsid();
+#ifdef TIOCSCTTY
+		buf = NULL;
+		if (ioctl(slave, TIOCSCTTY, NULL) < 0)
+			_exit(1);
+#elif defined(_AIX)
+		fd = open("/dev/tty", O_RDWR|O_NOCTTY);
+		if (fd >= 0)
+		{
+			ioctl(fd, TIOCNOTTY, NULL);
+			close(fd);
+		}
+
+		buf = ttyname(master);
+		fd = open(buf, O_RDWR);
+		close(fd);
+
+		fd = open("/dev/tty", O_WRONLY);
+		if (fd < 0)
+			_exit(1);
+		close(fd);
+
+		if (termp && tcsetattr(slave, TCSAFLUSH, termp) == -1)
+			_exit(1);
+		if (ioctl(slave, TIOCSWINSZ, winp) == -1)
+			_exit(1);
+#else
+		buf = ptsname(master);
+		fd = open(buf, O_RDWR);
+		close(fd);
+#endif
+		dup2(slave, 0);
+		dup2(slave, 1);
+		dup2(slave, 2);
+
+		if (slave > 2)
+			close(slave);
+		close(master);
+		return 0;
+	}
+	else
+	{
+		close(slave);
+		return pid;
+	}
+}
+#else
+#error Do not know how to define forkpty.
+#endif
+#endif