From d05debbe198699a84ddeaacfa4d5bf57e6afaac8 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Tue, 5 Mar 2013 18:00:14 +0000
Subject: [PATCH 01/17] Unzoom on last-pane and fix a typo, from Romain
 Francoise.

---
 cmd-select-pane.c | 1 +
 tmux.1            | 2 +-
 2 files changed, 2 insertions(+), 1 deletion(-)

diff --git a/cmd-select-pane.c b/cmd-select-pane.c
index d24d7b3d..b8a12671 100644
--- a/cmd-select-pane.c
+++ b/cmd-select-pane.c
@@ -80,6 +80,7 @@ cmd_select_pane_exec(struct cmd *self, struct cmd_q *cmdq)
 			return (CMD_RETURN_ERROR);
 		}
 
+		server_unzoom_window(wl->window);
 		window_set_active_pane(wl->window, wl->window->last);
 		server_status_window(wl->window);
 		server_redraw_window_borders(wl->window);
diff --git a/tmux.1 b/tmux.1
index a65ce221..1a9c0583 100644
--- a/tmux.1
+++ b/tmux.1
@@ -1619,7 +1619,7 @@ is given in lines or cells (the default is 1).
 .Pp
 With
 .Fl Z ,
-the active pane is toggled between occupying the whole of the window and it's
+the active pane is toggled between occupying the whole of the window and its
 normal position in the layout.
 .It Xo Ic respawn-pane
 .Op Fl k

From f9e46a373f1ac7155b77754b43b05ed885a9bec9 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Tue, 5 Mar 2013 20:01:16 +0000
Subject: [PATCH 02/17] Do not leak command in formats, from Romain Francoise.

---
 format.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/format.c b/format.c
index ad52caea..b711111b 100644
--- a/format.c
+++ b/format.c
@@ -398,7 +398,8 @@ format_window_pane(struct format_tree *ft, struct window_pane *wp)
 	struct grid_line	*gl;
 	unsigned long long	 size;
 	u_int			 i, idx;
-	const char		*cwd, *cmd;
+	const char		*cwd;
+	char			*cmd;
 
 	size = 0;
 	for (i = 0; i < gd->hsize; i++) {
@@ -432,8 +433,10 @@ format_window_pane(struct format_tree *ft, struct window_pane *wp)
 		format_add(ft, "pane_start_path", "%s", wp->cwd);
 	if ((cwd = osdep_get_cwd(wp->fd)) != NULL)
 		format_add(ft, "pane_current_path", "%s", cwd);
-	if ((cmd = osdep_get_name(wp->fd, wp->tty)) != NULL)
+	if ((cmd = osdep_get_name(wp->fd, wp->tty)) != NULL) {
 		format_add(ft, "pane_current_command", "%s", cmd);
+		free(cmd);
+	}
 
 	format_add(ft, "cursor_x", "%d", wp->base.cx);
 	format_add(ft, "cursor_y", "%d", wp->base.cy);

From ec75f9d1a36b6f46e7ec6597d295f113c4aa12b3 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Wed, 6 Mar 2013 09:56:31 +0000
Subject: [PATCH 03/17] Allow lastgc to be NULL in grid_string_cells so
 find-window doesn't crash, problem reported by eugene everson.

---
 grid.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/grid.c b/grid.c
index b30127f3..551a7dc9 100644
--- a/grid.c
+++ b/grid.c
@@ -595,7 +595,7 @@ grid_string_cells(struct grid *gd, u_int px, u_int py, u_int nx,
 
 	GRID_DEBUG(gd, "px=%u, py=%u, nx=%u", px, py, nx);
 
-	if (*lastgc == NULL) {
+	if (lastgc != NULL && *lastgc == NULL) {
 		memcpy(&lastgc1, &grid_default_cell, sizeof lastgc1);
 		*lastgc = &lastgc1;
 	}

From 7fd4d49d562d2f57e21d9198bc28914891478f7c Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Wed, 6 Mar 2013 09:57:26 +0000
Subject: [PATCH 04/17] Add a wait-for command which blocks a client on a named
 channel until it is wokrn up again (with wait-for -S). From Thiago Padilha.

---
 Makefile.am    |   1 +
 cmd-wait-for.c | 124 +++++++++++++++++++++++++++++++++++++++++++++++++
 cmd.c          |   1 +
 tmux.1         |  13 ++++++
 tmux.h         |   3 ++
 5 files changed, 142 insertions(+)
 create mode 100644 cmd-wait-for.c

diff --git a/Makefile.am b/Makefile.am
index 5caa4983..19220d8e 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -135,6 +135,7 @@ dist_tmux_SOURCES = \
 	cmd-switch-client.c \
 	cmd-unbind-key.c \
 	cmd-unlink-window.c \
+	cmd-wait-for.c \
 	cmd.c \
 	colour.c \
 	control.c \
diff --git a/cmd-wait-for.c b/cmd-wait-for.c
new file mode 100644
index 00000000..6313358a
--- /dev/null
+++ b/cmd-wait-for.c
@@ -0,0 +1,124 @@
+/* $Id$ */
+
+/*
+ * Copyright (c) 2013 Nicholas Marriott <nicm@users.sourceforge.net>
+ * Copyright (c) 2013 Thiago de Arruda <tpadilha84@gmail.com>
+ *
+ * Permission to use, copy, modify, and distribute this software for any
+ * purpose with or without fee is hereby granted, provided that the above
+ * copyright notice and this permission notice appear in all copies.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+ * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+ * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+ * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+ * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
+ * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
+ * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+ */
+
+#include <sys/types.h>
+
+#include <stdlib.h>
+#include <string.h>
+
+#include "tmux.h"
+
+/*
+ * Block or wake a client on a named wait channel.
+ */
+
+enum cmd_retval cmd_wait_for_exec(struct cmd *, struct cmd_q *);
+
+const struct cmd_entry cmd_wait_for_entry = {
+	"wait-for", "wait",
+	"S", 1, 1,
+	"[-S] channel",
+	0,
+	NULL,
+	NULL,
+	cmd_wait_for_exec
+};
+
+struct wait_channel {
+	const char	       *name;
+	TAILQ_HEAD(, cmd_q)	waiters;
+
+	RB_ENTRY(wait_channel)	entry;
+};
+RB_HEAD(wait_channels, wait_channel);
+struct wait_channels wait_channels = RB_INITIALIZER(wait_channels);
+
+int	wait_channel_cmp(struct wait_channel *, struct wait_channel *);
+RB_PROTOTYPE(wait_channels, wait_channel, entry, wait_channel_cmp);
+RB_GENERATE(wait_channels, wait_channel, entry, wait_channel_cmp);
+
+int
+wait_channel_cmp(struct wait_channel *wc1, struct wait_channel *wc2)
+{
+	return (strcmp(wc1->name, wc2->name));
+}
+
+enum cmd_retval	cmd_wait_for_signal(struct cmd_q *, const char *,
+		    struct wait_channel *);
+enum cmd_retval	cmd_wait_for_wait(struct cmd_q *, const char *,
+		    struct wait_channel *);
+
+enum cmd_retval
+cmd_wait_for_exec(struct cmd *self, struct cmd_q *cmdq)
+{
+	struct args     	*args = self->args;
+	const char		*name = args->argv[0];
+	struct wait_channel	*wc, wc0;
+
+	wc0.name = name;
+	wc = RB_FIND(wait_channels, &wait_channels, &wc0);
+
+	if (args_has(args, 'S'))
+		return (cmd_wait_for_signal(cmdq, name, wc));
+	return (cmd_wait_for_wait(cmdq, name, wc));
+}
+
+enum cmd_retval
+cmd_wait_for_signal(struct cmd_q *cmdq, const char *name,
+    struct wait_channel *wc)
+{
+	struct cmd_q	*wq, *wq1;
+
+	if (wc == NULL || TAILQ_EMPTY(&wc->waiters)) {
+		cmdq_error(cmdq, "no waiting clients on %s", name);
+		return (CMD_RETURN_ERROR);
+	}
+
+	TAILQ_FOREACH_SAFE(wq, &wc->waiters, waitentry, wq1) {
+		TAILQ_REMOVE(&wc->waiters, wq, waitentry);
+		if (!cmdq_free(wq))
+			cmdq_continue(wq);
+	}
+	RB_REMOVE(wait_channels, &wait_channels, wc);
+	free((void*) wc->name);
+	free(wc);
+
+	return (CMD_RETURN_NORMAL);
+}
+
+enum cmd_retval
+cmd_wait_for_wait(struct cmd_q *cmdq, const char *name,
+    struct wait_channel *wc)
+{
+	if (cmdq->client == NULL || cmdq->client->session != NULL) {
+		cmdq_error(cmdq, "not able to wait");
+		return (CMD_RETURN_ERROR);
+	}
+
+	if (wc == NULL) {
+		wc = xmalloc(sizeof *wc);
+		wc->name = xstrdup(name);
+		TAILQ_INIT(&wc->waiters);
+		RB_INSERT(wait_channels, &wait_channels, wc);
+	}
+	TAILQ_INSERT_TAIL(&wc->waiters, cmdq, waitentry);
+	cmdq->references++;
+
+	return (CMD_RETURN_WAIT);
+}
diff --git a/cmd.c b/cmd.c
index 0d6a85ff..20484ed8 100644
--- a/cmd.c
+++ b/cmd.c
@@ -112,6 +112,7 @@ const struct cmd_entry *cmd_table[] = {
 	&cmd_switch_client_entry,
 	&cmd_unbind_key_entry,
 	&cmd_unlink_window_entry,
+	&cmd_wait_for_entry,
 	NULL
 };
 
diff --git a/tmux.1 b/tmux.1
index 1a9c0583..8df7975e 100644
--- a/tmux.1
+++ b/tmux.1
@@ -3553,6 +3553,19 @@ If the command doesn't return success, the exit status is also displayed.
 .It Ic server-info
 .D1 (alias: Ic info )
 Show server information and terminal details.
+.It Xo Ic wait-for
+.Fl S
+.Ar channel
+.Xc
+.D1 (alias: Ic wait )
+When used without
+.Fl S ,
+prevents the client from exiting until woken using
+.Ic wait-for
+.Fl S
+with the same channel.
+This command only works from outside
+.Nm .
 .El
 .Sh TERMINFO EXTENSIONS
 .Nm
diff --git a/tmux.h b/tmux.h
index c1ad6628..e58c1dec 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1416,6 +1416,8 @@ struct cmd_q {
 	void			*data;
 
 	struct msg_command_data	*msgdata;
+
+	TAILQ_ENTRY(cmd_q)       waitentry;
 };
 
 /* Command definition. */
@@ -1835,6 +1837,7 @@ extern const struct cmd_entry cmd_switch_client_entry;
 extern const struct cmd_entry cmd_unbind_key_entry;
 extern const struct cmd_entry cmd_unlink_window_entry;
 extern const struct cmd_entry cmd_up_pane_entry;
+extern const struct cmd_entry cmd_wait_for_entry;
 
 /* cmd-attach-session.c */
 enum cmd_retval	 cmd_attach_session(struct cmd_q *, const char*, int, int);

From bc3580fa066ee38fd752b8414cb72af7bf3861b8 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Wed, 6 Mar 2013 11:00:55 +0000
Subject: [PATCH 05/17] Add wait-for -L and -U for lock and unlock, from Thiago
 Padilha.

---
 cmd-wait-for.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++---
 tmux.1         | 12 +++++---
 2 files changed, 86 insertions(+), 9 deletions(-)

diff --git a/cmd-wait-for.c b/cmd-wait-for.c
index 6313358a..d40ba49e 100644
--- a/cmd-wait-for.c
+++ b/cmd-wait-for.c
@@ -32,8 +32,8 @@ enum cmd_retval cmd_wait_for_exec(struct cmd *, struct cmd_q *);
 
 const struct cmd_entry cmd_wait_for_entry = {
 	"wait-for", "wait",
-	"S", 1, 1,
-	"[-S] channel",
+	"LSU", 1, 1,
+	"[-LSU] channel",
 	0,
 	NULL,
 	NULL,
@@ -42,7 +42,10 @@ const struct cmd_entry cmd_wait_for_entry = {
 
 struct wait_channel {
 	const char	       *name;
+	int			locked;
+
 	TAILQ_HEAD(, cmd_q)	waiters;
+	TAILQ_HEAD(, cmd_q)	lockers;
 
 	RB_ENTRY(wait_channel)	entry;
 };
@@ -63,6 +66,10 @@ enum cmd_retval	cmd_wait_for_signal(struct cmd_q *, const char *,
 		    struct wait_channel *);
 enum cmd_retval	cmd_wait_for_wait(struct cmd_q *, const char *,
 		    struct wait_channel *);
+enum cmd_retval	cmd_wait_for_lock(struct cmd_q *, const char *,
+		    struct wait_channel *);
+enum cmd_retval	cmd_wait_for_unlock(struct cmd_q *, const char *,
+		    struct wait_channel *);
 
 enum cmd_retval
 cmd_wait_for_exec(struct cmd *self, struct cmd_q *cmdq)
@@ -76,6 +83,10 @@ cmd_wait_for_exec(struct cmd *self, struct cmd_q *cmdq)
 
 	if (args_has(args, 'S'))
 		return (cmd_wait_for_signal(cmdq, name, wc));
+	if (args_has(args, 'L'))
+		return (cmd_wait_for_lock(cmdq, name, wc));
+	if (args_has(args, 'U'))
+		return (cmd_wait_for_unlock(cmdq, name, wc));
 	return (cmd_wait_for_wait(cmdq, name, wc));
 }
 
@@ -95,9 +106,12 @@ cmd_wait_for_signal(struct cmd_q *cmdq, const char *name,
 		if (!cmdq_free(wq))
 			cmdq_continue(wq);
 	}
-	RB_REMOVE(wait_channels, &wait_channels, wc);
-	free((void*) wc->name);
-	free(wc);
+
+	if (!wc->locked) {
+		RB_REMOVE(wait_channels, &wait_channels, wc);
+		free((void*) wc->name);
+		free(wc);
+	}
 
 	return (CMD_RETURN_NORMAL);
 }
@@ -114,11 +128,70 @@ cmd_wait_for_wait(struct cmd_q *cmdq, const char *name,
 	if (wc == NULL) {
 		wc = xmalloc(sizeof *wc);
 		wc->name = xstrdup(name);
+		wc->locked = 0;
 		TAILQ_INIT(&wc->waiters);
+		TAILQ_INIT(&wc->lockers);
 		RB_INSERT(wait_channels, &wait_channels, wc);
 	}
+
 	TAILQ_INSERT_TAIL(&wc->waiters, cmdq, waitentry);
 	cmdq->references++;
 
 	return (CMD_RETURN_WAIT);
 }
+
+enum cmd_retval
+cmd_wait_for_lock(struct cmd_q *cmdq, const char *name,
+    struct wait_channel *wc)
+{
+	if (cmdq->client == NULL || cmdq->client->session != NULL) {
+		cmdq_error(cmdq, "not able to lock");
+		return (CMD_RETURN_ERROR);
+	}
+
+	if (wc == NULL) {
+		wc = xmalloc(sizeof *wc);
+		wc->name = xstrdup(name);
+		wc->locked = 0;
+		TAILQ_INIT(&wc->waiters);
+		TAILQ_INIT(&wc->lockers);
+		RB_INSERT(wait_channels, &wait_channels, wc);
+	}
+
+	if (wc->locked) {
+		TAILQ_INSERT_TAIL(&wc->lockers, cmdq, waitentry);
+		cmdq->references++;
+		return (CMD_RETURN_WAIT);
+	}
+	wc->locked = 1;
+
+	return (CMD_RETURN_NORMAL);
+}
+
+enum cmd_retval
+cmd_wait_for_unlock(struct cmd_q *cmdq, const char *name,
+    struct wait_channel *wc)
+{
+	struct cmd_q	*wq;
+
+	if (wc == NULL || !wc->locked) {
+		cmdq_error(cmdq, "channel %s not locked", name);
+		return (CMD_RETURN_ERROR);
+	}
+
+	if ((wq = TAILQ_FIRST(&wc->lockers)) != NULL) {
+		TAILQ_REMOVE(&wc->lockers, wq, waitentry);
+		if (!cmdq_free(wq))
+			cmdq_continue(wq);
+	} else {
+		wc->locked = 0;
+		if (TAILQ_EMPTY(&wc->waiters)) {
+			RB_REMOVE(wait_channels, &wait_channels, wc);
+			free((void*) wc->name);
+			free(wc);
+		}
+	}
+
+	return (CMD_RETURN_NORMAL);
+}
+
diff --git a/tmux.1 b/tmux.1
index 8df7975e..0b5d6a6a 100644
--- a/tmux.1
+++ b/tmux.1
@@ -3554,16 +3554,20 @@ If the command doesn't return success, the exit status is also displayed.
 .D1 (alias: Ic info )
 Show server information and terminal details.
 .It Xo Ic wait-for
-.Fl S
+.Fl LSU
 .Ar channel
 .Xc
 .D1 (alias: Ic wait )
-When used without
-.Fl S ,
-prevents the client from exiting until woken using
+When used without options, prevents the client from exiting until woken using
 .Ic wait-for
 .Fl S
 with the same channel.
+When
+.Fl L
+is used, the channel is locked and any clients that try to lock the same
+channel are made to wait until the channel is unlocked with
+.Ic wait-for
+.Fl U .
 This command only works from outside
 .Nm .
 .El

From e964ff70e696f30f0301d11deb45c8ada54e0c55 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Wed, 6 Mar 2013 14:58:48 +0000
Subject: [PATCH 06/17] Fix --disable-static, reported by Shea Levy.

---
 configure.ac | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/configure.ac b/configure.ac
index 84aec0fb..9e060df7 100644
--- a/configure.ac
+++ b/configure.ac
@@ -53,8 +53,11 @@ AM_CONDITIONAL(IS_DEBUG, test "x$found_debug" = xyes)
 AC_ARG_ENABLE(
        static,
        AC_HELP_STRING(--enable-static, create a static build),
-       [LDFLAGS="$LDFLAGS -static"]
+       found_static=$enable_static
 )
+if test "x$found_static" = xyes; then
+   LDFLAGS="$LDFLAGS -static"
+fi
 
 # Is this gcc?
 AM_CONDITIONAL(IS_GCC, test "x$GCC" = xyes)

From f47a063841f2baa1590fb9e53713b3713a03020d Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Thu, 7 Mar 2013 10:07:22 +0000
Subject: [PATCH 07/17] Rename session idx to session id throughout and add $
 prefix to targets to use it, extended from a diff from George Nachman.

---
 client.c          |  2 +-
 cmd-server-info.c |  2 +-
 cmd.c             | 24 ++++++++++++++++++++++--
 control-notify.c  |  2 +-
 format.c          |  1 +
 server-fn.c       |  2 +-
 session.c         | 14 +++++++-------
 tmux.1            |  5 +++--
 tmux.c            |  8 ++++----
 tmux.h            | 10 +++++-----
 window-choose.c   |  2 +-
 11 files changed, 47 insertions(+), 25 deletions(-)

diff --git a/client.c b/client.c
index 5b227b44..56caa338 100644
--- a/client.c
+++ b/client.c
@@ -270,7 +270,7 @@ client_main(int argc, char **argv, int flags)
 	if (msg == MSG_COMMAND) {
 		/* Fill in command line arguments. */
 		cmddata.pid = environ_pid;
-		cmddata.idx = environ_idx;
+		cmddata.session_id = environ_session_id;
 
 		/* Prepare command for server. */
 		cmddata.argc = argc;
diff --git a/cmd-server-info.c b/cmd-server-info.c
index b044649c..8eba172a 100644
--- a/cmd-server-info.c
+++ b/cmd-server-info.c
@@ -102,7 +102,7 @@ cmd_server_info_exec(unused struct cmd *self, struct cmd_q *cmdq)
 		*strchr(tim, '\n') = '\0';
 
 		cmdq_print(cmdq, "%2u: %s: %u windows (created %s) [%ux%u] "
-		    "[flags=0x%x]", s->idx, s->name,
+		    "[flags=0x%x]", s->id, s->name,
 		    winlink_count(&s->windows), tim, s->sx, s->sy, s->flags);
 		RB_FOREACH(wl, winlinks, &s->windows) {
 			w = wl->window;
diff --git a/cmd.c b/cmd.c
index 20484ed8..c8e9702d 100644
--- a/cmd.c
+++ b/cmd.c
@@ -122,6 +122,7 @@ struct session	*cmd_choose_session(int);
 struct client	*cmd_choose_client(struct clients *);
 struct client	*cmd_lookup_client(const char *);
 struct session	*cmd_lookup_session(const char *, int *);
+struct session	*cmd_lookup_session_id(const char *);
 struct winlink	*cmd_lookup_window(struct session *, const char *, int *);
 int		 cmd_lookup_index(struct session *, const char *, int *);
 struct window_pane *cmd_lookup_paneid(const char *);
@@ -357,8 +358,8 @@ cmd_current_session(struct cmd_q *cmdq, int prefer_unattached)
 	}
 
 	/* Use the session from the TMUX environment variable. */
-	if (data != NULL && data->pid == getpid() && data->idx != -1) {
-		s = session_find_by_index(data->idx);
+	if (data != NULL && data->pid == getpid() && data->session_id != -1) {
+		s = session_find_by_id(data->session_id);
 		if (s != NULL)
 			return (s);
 	}
@@ -550,6 +551,21 @@ cmd_lookup_client(const char *name)
 	return (NULL);
 }
 
+/* Find the target session or report an error and return NULL. */
+struct session *
+cmd_lookup_session_id(const char *arg)
+{
+	char	*endptr;
+	long	 id;
+
+	if (arg[0] != '$')
+		return (NULL);
+	id = strtol(arg + 1, &endptr, 10);
+	if (arg[1] != '\0' && *endptr == '\0')
+		return (session_find_by_id(id));
+	return (NULL);
+}
+
 /* Lookup a session by name. If no session is found, NULL is returned. */
 struct session *
 cmd_lookup_session(const char *name, int *ambiguous)
@@ -558,6 +574,10 @@ cmd_lookup_session(const char *name, int *ambiguous)
 
 	*ambiguous = 0;
 
+	/* Look for $id first. */
+	if ((s = cmd_lookup_session_id(name)) != NULL)
+		return (s);
+
 	/*
 	 * Look for matches. First look for exact matches - session names must
 	 * be unique so an exact match can't be ambigious and can just be
diff --git a/control-notify.c b/control-notify.c
index bb9708c8..6bc98b6f 100644
--- a/control-notify.c
+++ b/control-notify.c
@@ -154,7 +154,7 @@ control_notify_attached_session_changed(struct client *c)
 		return;
 	s = c->session;
 
-	control_write(c, "%%session-changed %d %s", s->idx, s->name);
+	control_write(c, "%%session-changed %d %s", s->id, s->name);
 }
 
 void
diff --git a/format.c b/format.c
index b711111b..4d70d59b 100644
--- a/format.c
+++ b/format.c
@@ -280,6 +280,7 @@ format_session(struct format_tree *ft, struct session *s)
 	format_add(ft, "session_windows", "%u", winlink_count(&s->windows));
 	format_add(ft, "session_width", "%u", s->sx);
 	format_add(ft, "session_height", "%u", s->sy);
+	format_add(ft, "session_id", "%u", s->id);
 
 	sg = session_group_find(s);
 	format_add(ft, "session_grouped", "%d", sg != NULL);
diff --git a/server-fn.c b/server-fn.c
index b09415e0..4d8a658c 100644
--- a/server-fn.c
+++ b/server-fn.c
@@ -39,7 +39,7 @@ server_fill_environ(struct session *s, struct environ *env)
 		term = options_get_string(&s->options, "default-terminal");
 		environ_set(env, "TERM", term);
 
-		idx = s->idx;
+		idx = s->id;
 	} else
 		idx = -1;
 	pid = getpid();
diff --git a/session.c b/session.c
index 72e8fb05..74eb06a5 100644
--- a/session.c
+++ b/session.c
@@ -29,7 +29,7 @@
 /* Global session list. */
 struct sessions	sessions;
 struct sessions dead_sessions;
-u_int		next_session;
+u_int		next_session_id;
 struct session_groups session_groups;
 
 struct winlink *session_next_alert(struct winlink *);
@@ -69,14 +69,14 @@ session_find(const char *name)
 	return (RB_FIND(sessions, &sessions, &s));
 }
 
-/* Find session by index. */
+/* Find session by id. */
 struct session *
-session_find_by_index(u_int idx)
+session_find_by_id(u_int id)
 {
 	struct session	*s;
 
 	RB_FOREACH(s, sessions, &sessions) {
-		if (s->idx == idx)
+		if (s->id == id)
 			return (s);
 	}
 	return (NULL);
@@ -120,13 +120,13 @@ session_create(const char *name, const char *cmd, const char *cwd,
 
 	if (name != NULL) {
 		s->name = xstrdup(name);
-		s->idx = next_session++;
+		s->id = next_session_id++;
 	} else {
 		s->name = NULL;
 		do {
-			s->idx = next_session++;
+			s->id = next_session_id++;
 			free (s->name);
-			xasprintf(&s->name, "%u", s->idx);
+			xasprintf(&s->name, "%u", s->id);
 		} while (RB_FIND(sessions, &sessions, s) != NULL);
 	}
 	RB_INSERT(sessions, &sessions, s);
diff --git a/tmux.1 b/tmux.1
index 0b5d6a6a..f219615e 100644
--- a/tmux.1
+++ b/tmux.1
@@ -369,9 +369,9 @@ Clients may be listed with the
 command.
 .Pp
 .Ar target-session
-is either the name of a session (as listed by the
+is the session id prefixed with a $, the name of a session (as listed by the
 .Ic list-sessions
-command) or the name of a client with the same syntax as
+command), or the name of a client with the same syntax as
 .Ar target-client ,
 in which case the session attached to the client is used.
 When looking for the session name,
@@ -3085,6 +3085,7 @@ The following variables are available, where appropriate:
 .It Li "session_group" Ta "Number of session group"
 .It Li "session_grouped" Ta "1 if session in a group"
 .It Li "session_height" Ta "Height of session"
+.It Li "session_id" Ta "Unique session ID"
 .It Li "session_name" Ta "Name of session"
 .It Li "session_width" Ta "Width of session"
 .It Li "session_windows" Ta "Number of windows in session"
diff --git a/tmux.c b/tmux.c
index f6856605..8ea91ebe 100644
--- a/tmux.c
+++ b/tmux.c
@@ -48,7 +48,7 @@ char		 socket_path[MAXPATHLEN];
 int		 login_shell;
 char		*environ_path;
 pid_t		 environ_pid = -1;
-int		 environ_idx = -1;
+int		 environ_session_id = -1;
 
 __dead void	 usage(void);
 void	 	 parseenvironment(void);
@@ -147,16 +147,16 @@ parseenvironment(void)
 {
 	char	*env, path[256];
 	long	 pid;
-	int	 idx;
+	int	 id;
 
 	if ((env = getenv("TMUX")) == NULL)
 		return;
 
-	if (sscanf(env, "%255[^,],%ld,%d", path, &pid, &idx) != 3)
+	if (sscanf(env, "%255[^,],%ld,%d", path, &pid, &id) != 3)
 		return;
 	environ_path = xstrdup(path);
 	environ_pid = pid;
-	environ_idx = idx;
+	environ_session_id = id;
 }
 
 char *
diff --git a/tmux.h b/tmux.h
index e58c1dec..e45cd487 100644
--- a/tmux.h
+++ b/tmux.h
@@ -462,8 +462,8 @@ enum msgtype {
  * Don't forget to bump PROTOCOL_VERSION if any of these change!
  */
 struct msg_command_data {
-	pid_t		pid;	/* PID from $TMUX or -1 */
-	int		idx;	/* index from $TMUX or -1 */
+	pid_t		pid;		/* from $TMUX or -1 */
+	int		session_id;	/* from $TMUX or -1 */
 
 	int		argc;
 	char		argv[COMMAND_LENGTH];
@@ -1086,7 +1086,7 @@ struct session_group {
 TAILQ_HEAD(session_groups, session_group);
 
 struct session {
-	u_int		 idx;
+	u_int		 id;
 
 	char		*name;
 	char		*cwd;
@@ -1513,7 +1513,7 @@ extern char	 socket_path[MAXPATHLEN];
 extern int	 login_shell;
 extern char	*environ_path;
 extern pid_t	 environ_pid;
-extern int	 environ_idx;
+extern int	 environ_session_id;
 void		 logfile(const char *);
 const char	*getshell(void);
 int		 checkshell(const char *);
@@ -2287,7 +2287,7 @@ int	session_cmp(struct session *, struct session *);
 RB_PROTOTYPE(sessions, session, entry, session_cmp);
 int		 session_alive(struct session *);
 struct session	*session_find(const char *);
-struct session	*session_find_by_index(u_int);
+struct session	*session_find_by_id(u_int);
 struct session	*session_create(const char *, const char *, const char *,
 		     struct environ *, struct termios *, int, u_int, u_int,
 		     char **);
diff --git a/window-choose.c b/window-choose.c
index b56b2022..3c68d101 100644
--- a/window-choose.c
+++ b/window-choose.c
@@ -859,7 +859,7 @@ window_choose_add_session(struct window_pane *wp, struct client *c,
 	struct window_choose_data	*wcd;
 
 	wcd = window_choose_data_create(TREE_SESSION, c, c->session);
-	wcd->idx = s->idx;
+	wcd->idx = s->id;
 
 	wcd->tree_session = s;
 	wcd->tree_session->references++;

From dde5d49a5ed305cfa32f18c08d6f1b769d8ccef7 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Sat, 9 Mar 2013 17:29:22 +0000
Subject: [PATCH 08/17] Do not redraw panes if invisible.

---
 screen-redraw.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/screen-redraw.c b/screen-redraw.c
index 899f741b..14b73164 100644
--- a/screen-redraw.c
+++ b/screen-redraw.c
@@ -273,6 +273,9 @@ screen_redraw_pane(struct client *c, struct window_pane *wp)
 {
 	u_int	i, yoff;
 
+	if (!window_pane_visible(wp))
+		return;
+
 	yoff = wp->yoff;
 	if (status_at_line(c) == 0)
 		yoff++;

From 06ac399ce6dc25201cfd1670b08ed8758034e2dc Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Sat, 9 Mar 2013 21:32:47 +0000
Subject: [PATCH 09/17] Zoom script is no longer needed.

---
 examples/tmux-zoom.sh | 57 -------------------------------------------
 1 file changed, 57 deletions(-)
 delete mode 100644 examples/tmux-zoom.sh

diff --git a/examples/tmux-zoom.sh b/examples/tmux-zoom.sh
deleted file mode 100644
index 3a604564..00000000
--- a/examples/tmux-zoom.sh
+++ /dev/null
@@ -1,57 +0,0 @@
-#!/bin/bash
-
-# Copyright (c) 2012 Juan Ignacio Pumarino, jipumarino@gmail.com
-# 
-# Permission is hereby granted, free of charge, to any person obtaining
-# a copy of this software and associated documentation files (the
-# "Software"), to deal in the Software without restriction, including
-# without limitation the rights to use, copy, modify, merge, publish,
-# distribute, sublicense, and/or sell copies of the Software, and to
-# permit persons to whom the Software is furnished to do so, subject to
-# the following conditions:
-# 
-# The above copyright notice and this permission notice shall be
-# included in all copies or substantial portions of the Software.
-# 
-# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
-# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
-# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
-# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
-# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
-# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
-# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
-
-# Instructions
-# ------------
-#
-# 1. Install this script and give it execute permission somewhere in your PATH.
-#    For example:
-#
-#    $ mkdir -p ~/bin
-#    $ wget https://raw.github.com/jipumarino/tmux-zoom/master/tmux-zoom.sh -O ~/bin/tmux-zoom.sh
-#    $ chmod +x ~/bin/tmux-zoom.sh
-# 
-# 2. Add a shortcut in your ~/.tmux.conf file:
-#
-#    bind C-k run "tmux-zoom.sh"
-#
-# 3. When using this shortcut, the current tmux pane will open in a new window by itself.
-#    Running it again in the zoomed window will return it to its original pane. You can have
-#    as many zoomed windows as you want.
-
-current=$(tmux display-message -p '#W-#I-#P')
-list=$(tmux list-window)
-
-[[ "$current" =~ ^(.*)-([0-9]+)-([0-9]+) ]]
-current_window=${BASH_REMATCH[1]}
-current_pane=${BASH_REMATCH[2]}-${BASH_REMATCH[3]}
-new_zoom_window=ZOOM-$current_pane
-
-if [[ $current_window =~ ZOOM-([0-9]+)-([0-9+]) ]]; then
-  old_zoom_window=ZOOM-${BASH_REMATCH[1]}-${BASH_REMATCH[2]}
-  tmux select-window -t ${BASH_REMATCH[1]} \; select-pane -t ${BASH_REMATCH[2]} \; swap-pane -s $old_zoom_window.1 \; kill-window -t $old_zoom_window
-elif [[ $list =~ $new_zoom_window ]]; then
-  tmux select-window -t $new_zoom_window
-else
-  tmux new-window -d -n $new_zoom_window \; swap-pane -s $new_zoom_window.1 \; select-window -t $new_zoom_window
-fi

From a060aa2bf091c7befbb37f86ef450cd575a3e53e Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Sun, 10 Mar 2013 23:41:59 +0000
Subject: [PATCH 10/17] Fix handling of short (< 4 character) checksums and a
 bug with parsing old-style custom layouts. Based on fix from Chris Johnsen.

---
 layout-custom.c | 9 ++++++---
 1 file changed, 6 insertions(+), 3 deletions(-)

diff --git a/layout-custom.c b/layout-custom.c
index c076232f..e32d9d9d 100644
--- a/layout-custom.c
+++ b/layout-custom.c
@@ -63,7 +63,7 @@ layout_dump(struct window *w)
 	if (layout_append(w->layout_root, layout, sizeof layout) != 0)
 		return (NULL);
 
-	xasprintf(&out, "%4x,%s", layout_checksum(layout), layout);
+	xasprintf(&out, "%04x,%s", layout_checksum(layout), layout);
 	return (out);
 }
 
@@ -206,11 +206,11 @@ layout_construct(struct layout_cell *lcparent, const char **layout)
 {
 	struct layout_cell     *lc, *lcchild;
 	u_int			sx, sy, xoff, yoff;
+	const char	       *saved;
 
 	if (!isdigit((u_char) **layout))
 		return (NULL);
-	if (sscanf(*layout, "%ux%u,%u,%u,%*u", &sx, &sy, &xoff, &yoff) != 4 &&
-	    sscanf(*layout, "%ux%u,%u,%u", &sx, &sy, &xoff, &yoff) != 4)
+	if (sscanf(*layout, "%ux%u,%u,%u", &sx, &sy, &xoff, &yoff) != 4)
 		return (NULL);
 
 	while (isdigit((u_char) **layout))
@@ -231,9 +231,12 @@ layout_construct(struct layout_cell *lcparent, const char **layout)
 	while (isdigit((u_char) **layout))
 		(*layout)++;
 	if (**layout == ',') {
+		saved = *layout;
 		(*layout)++;
 		while (isdigit((u_char) **layout))
 			(*layout)++;
+		if (**layout == 'x')
+			*layout = saved;
 	}
 
 	lc = layout_create_cell(lcparent);

From c41d92d27a8083286793a58bc02ffc015d8c70ac Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 09:35:44 +0000
Subject: [PATCH 11/17] Add time and a command count to control mode guards,
 based on code from George Nachman.

---
 cmd-queue.c | 39 +++++++++++++++++++++++++--------------
 control.c   |  9 +++++++--
 tmux.h      |  4 ++++
 3 files changed, 36 insertions(+), 16 deletions(-)

diff --git a/cmd-queue.c b/cmd-queue.c
index 4b00fceb..52674442 100644
--- a/cmd-queue.c
+++ b/cmd-queue.c
@@ -151,6 +151,22 @@ cmdq_error(struct cmd_q *cmdq, const char *fmt, ...)
 	free(msg);
 }
 
+/* Print a guard line. */
+void
+cmdq_guard(struct cmd_q *cmdq, const char *guard)
+{
+	struct client	*c = cmdq->client;
+
+	if (c == NULL || c->session == NULL)
+		return;
+	if (!(c->flags & CLIENT_CONTROL))
+		return;
+
+	evbuffer_add_printf(c->stdout_data, "%%%s %ld %u\n", guard,
+	    cmdq->time, cmdq->number);
+	server_push_stdout(c);
+}
+
 /* Add command list to queue and begin processing if needed. */
 void
 cmdq_run(struct cmd_q *cmdq, struct cmd_list *cmdlist)
@@ -179,16 +195,11 @@ cmdq_append(struct cmd_q *cmdq, struct cmd_list *cmdlist)
 int
 cmdq_continue(struct cmd_q *cmdq)
 {
-	struct client		*c = cmdq->client;
 	struct cmd_q_item	*next;
 	enum cmd_retval		 retval;
-	int			 guards, empty;
+	int			 empty;
 	char			 s[1024];
 
-	guards = 0;
-	if (c != NULL && c->session != NULL)
-		guards = c->flags & CLIENT_CONTROL;
-
 	notify_disable();
 
 	empty = TAILQ_EMPTY(&cmdq->queue);
@@ -209,15 +220,15 @@ cmdq_continue(struct cmd_q *cmdq)
 			log_debug("cmdq %p: %s (client %d)", cmdq, s,
 			    cmdq->client != NULL ? cmdq->client->ibuf.fd : -1);
 
-			if (guards)
-				cmdq_print(cmdq, "%%begin");
+			cmdq->time = time(NULL);
+			cmdq->number++;
+
+			cmdq_guard(cmdq, "begin");
 			retval = cmdq->cmd->entry->exec(cmdq->cmd, cmdq);
-			if (guards) {
-				if (retval == CMD_RETURN_ERROR)
-					cmdq_print(cmdq, "%%error");
-				else
-					cmdq_print(cmdq, "%%end");
-			}
+			if (retval == CMD_RETURN_ERROR)
+				cmdq_guard(cmdq, "error");
+			else
+				cmdq_guard(cmdq, "end");
 
 			if (retval == CMD_RETURN_ERROR)
 				break;
diff --git a/control.c b/control.c
index 06f20bbb..c888877e 100644
--- a/control.c
+++ b/control.c
@@ -68,8 +68,13 @@ control_callback(struct client *c, int closed, unused void *data)
 		}
 
 		if (cmd_string_parse(line, &cmdlist, NULL, 0, &cause) != 0) {
-			control_write(c, "%%error in line \"%s\": %s", line,
-			    cause);
+			c->cmdq->time = time(NULL);
+			c->cmdq->number++;
+
+			cmdq_guard(c->cmdq, "begin");
+			control_write(c, "parse error: %s", cause);
+			cmdq_guard(c->cmdq, "error");
+
 			free(cause);
 		} else {
 			cmdq_run(c->cmdq, cmdlist);
diff --git a/tmux.h b/tmux.h
index e45cd487..89860cb8 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1412,6 +1412,9 @@ struct cmd_q {
 	struct cmd_q_item	*item;
 	struct cmd		*cmd;
 
+	time_t			 time;
+	u_int			 number;
+
 	void			 (*emptyfn)(struct cmd_q *);
 	void			*data;
 
@@ -1853,6 +1856,7 @@ int		 cmdq_free(struct cmd_q *);
 void printflike2 cmdq_print(struct cmd_q *, const char *, ...);
 void printflike2 cmdq_info(struct cmd_q *, const char *, ...);
 void printflike2 cmdq_error(struct cmd_q *, const char *, ...);
+void		 cmdq_guard(struct cmd_q *, const char *);
 void		 cmdq_run(struct cmd_q *, struct cmd_list *);
 void		 cmdq_append(struct cmd_q *, struct cmd_list *);
 int		 cmdq_continue(struct cmd_q *);

From 49ed75d88369ae8a3203cdce7fa537c792f4ba69 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 09:37:16 +0000
Subject: [PATCH 12/17] Fix a warning.

---
 cmd-queue.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/cmd-queue.c b/cmd-queue.c
index 52674442..17992a37 100644
--- a/cmd-queue.c
+++ b/cmd-queue.c
@@ -163,7 +163,7 @@ cmdq_guard(struct cmd_q *cmdq, const char *guard)
 		return;
 
 	evbuffer_add_printf(c->stdout_data, "%%%s %ld %u\n", guard,
-	    cmdq->time, cmdq->number);
+	    (long) cmdq->time, cmdq->number);
 	server_push_stdout(c);
 }
 

From 97620bb5becf29571a8f5bd1ee89e0b12908f799 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 09:37:52 +0000
Subject: [PATCH 13/17] Add a home and end as modified by xterm in keypad mode,
 from Chris Johnsen.

---
 tty-keys.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/tty-keys.c b/tty-keys.c
index 575920e6..fab8c3fb 100644
--- a/tty-keys.c
+++ b/tty-keys.c
@@ -82,6 +82,13 @@ const struct tty_default_key_raw tty_default_raw_keys[] = {
 	{ "\033[C", KEYC_RIGHT },
 	{ "\033[D", KEYC_LEFT },
 
+	/* Other (xterm) "cursor" keys. */
+	{ "\033OH", KEYC_HOME },
+	{ "\033OF", KEYC_END },
+
+	{ "\033[H", KEYC_HOME },
+	{ "\033[F", KEYC_END },
+
 	/* rxvt-style arrow + modifier keys. */
 	{ "\033Oa", KEYC_UP|KEYC_CTRL },
 	{ "\033Ob", KEYC_DOWN|KEYC_CTRL },

From a6ad44f111a42553ad38a850a0e215914ea1f037 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 09:43:56 +0000
Subject: [PATCH 14/17] Fix if-shell and run-shell if there are no sessions.
 Batted around through several people, finished off by Chris Johnsen.

---
 cmd-if-shell.c  | 20 +++++++++++---------
 cmd-run-shell.c | 29 ++++++++++++++++-------------
 2 files changed, 27 insertions(+), 22 deletions(-)

diff --git a/cmd-if-shell.c b/cmd-if-shell.c
index b921f418..b22e3269 100644
--- a/cmd-if-shell.c
+++ b/cmd-if-shell.c
@@ -59,19 +59,21 @@ cmd_if_shell_exec(struct cmd *self, struct cmd_q *cmdq)
 	struct args			*args = self->args;
 	struct cmd_if_shell_data	*cdata;
 	char				*shellcmd;
-	struct session			*s;
-	struct winlink			*wl;
-	struct window_pane		*wp;
+	struct session			*s = NULL;
+	struct winlink			*wl = NULL;
+	struct window_pane		*wp = NULL;
 	struct format_tree		*ft;
 
-	wl = cmd_find_pane(cmdq, args_get(args, 't'), &s, &wp);
-	if (wl == NULL)
-		return (CMD_RETURN_ERROR);
+	if (args_has(args, 't'))
+		wl = cmd_find_pane(cmdq, args_get(args, 't'), &s, &wp);
 
 	ft = format_create();
-	format_session(ft, s);
-	format_winlink(ft, s, wl);
-	format_window_pane(ft, wp);
+	if (s != NULL)
+		format_session(ft, s);
+	if (s != NULL && wl != NULL)
+		format_winlink(ft, s, wl);
+	if (wp != NULL)
+		format_window_pane(ft, wp);
 	shellcmd = format_expand(ft, args->argv[0]);
 	format_free(ft);
 
diff --git a/cmd-run-shell.c b/cmd-run-shell.c
index aaa310b9..b163542f 100644
--- a/cmd-run-shell.c
+++ b/cmd-run-shell.c
@@ -49,16 +49,17 @@ struct cmd_run_shell_data {
 	char		*cmd;
 	struct cmd_q	*cmdq;
 	int		 bflag;
-	u_int		 wp_id;
+	int		 wp_id;
 };
 
 void
 cmd_run_shell_print(struct job *job, const char *msg)
 {
 	struct cmd_run_shell_data	*cdata = job->data;
-	struct window_pane		*wp;
+	struct window_pane		*wp = NULL;
 
-	wp = window_pane_find_by_id(cdata->wp_id);
+	if (cdata->wp_id != -1)
+		wp = window_pane_find_by_id(cdata->wp_id);
 	if (wp == NULL) {
 		cmdq_print(cdata->cmdq, "%s", msg);
 		return;
@@ -76,26 +77,28 @@ cmd_run_shell_exec(struct cmd *self, struct cmd_q *cmdq)
 	struct args			*args = self->args;
 	struct cmd_run_shell_data	*cdata;
 	char				*shellcmd;
-	struct session			*s;
-	struct winlink			*wl;
-	struct window_pane		*wp;
+	struct session			*s = NULL;
+	struct winlink			*wl = NULL;
+	struct window_pane		*wp = NULL;
 	struct format_tree		*ft;
 
-	wl = cmd_find_pane(cmdq, args_get(args, 't'), &s, &wp);
-	if (wl == NULL)
-		return (CMD_RETURN_ERROR);
+	if (args_has(args, 't'))
+		wl = cmd_find_pane(cmdq, args_get(args, 't'), &s, &wp);
 
 	ft = format_create();
-	format_session(ft, s);
-	format_winlink(ft, s, wl);
-	format_window_pane(ft, wp);
+	if (s != NULL)
+		format_session(ft, s);
+	if (s != NULL && wl != NULL)
+		format_winlink(ft, s, wl);
+	if (wp != NULL)
+		format_window_pane(ft, wp);
 	shellcmd = format_expand(ft, args->argv[0]);
 	format_free(ft);
 
 	cdata = xmalloc(sizeof *cdata);
 	cdata->cmd = shellcmd;
 	cdata->bflag = args_has(args, 'b');
-	cdata->wp_id = wp->id;
+	cdata->wp_id = wp != NULL ? (int) wp->id : -1;
 
 	cdata->cmdq = cmdq;
 	cmdq->references++;

From 412ac6bc3a690628f72101494ac88e91c7d3377c Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 09:46:18 +0000
Subject: [PATCH 15/17] Use single stdout and stderr for control clients.

---
 server-client.c | 5 ++++-
 server-fn.c     | 4 ++++
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/server-client.c b/server-client.c
index b905a7c7..77e6de78 100644
--- a/server-client.c
+++ b/server-client.c
@@ -153,7 +153,8 @@ server_client_lost(struct client *c)
 
 	evbuffer_free (c->stdin_data);
 	evbuffer_free (c->stdout_data);
-	evbuffer_free (c->stderr_data);
+	if (c->stderr_data != c->stdout_data)
+		evbuffer_free (c->stderr_data);
 
 	status_free_jobs(&c->status_new);
 	status_free_jobs(&c->status_old);
@@ -955,6 +956,8 @@ server_client_msg_identify(
 
 	if (data->flags & IDENTIFY_CONTROL) {
 		c->stdin_callback = control_callback;
+		evbuffer_free(c->stderr_data);
+		c->stderr_data = c->stdout_data;
 		c->flags |= CLIENT_CONTROL;
 		if (data->flags & IDENTIFY_TERMIOS)
 			evbuffer_add_printf(c->stdout_data, "\033P1000p");
diff --git a/server-fn.c b/server-fn.c
index 4d8a658c..566925f0 100644
--- a/server-fn.c
+++ b/server-fn.c
@@ -546,6 +546,10 @@ server_push_stderr(struct client *c)
 	struct msg_stderr_data data;
 	size_t                 size;
 
+	if (c->stderr_data == c->stdout_data) {
+		server_push_stdout(c);
+		return;
+	}
 	size = EVBUFFER_LENGTH(c->stderr_data);
 	if (size == 0)
 		return;

From 7b4084a15a5c82824737051143dfe0115cff52e5 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 13:06:30 +0000
Subject: [PATCH 16/17] Document control mode in the manpage, from George
 Nachman.

---
 tmux.1 | 95 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++-
 1 file changed, 94 insertions(+), 1 deletion(-)

diff --git a/tmux.1 b/tmux.1
index f219615e..f73af3fa 100644
--- a/tmux.1
+++ b/tmux.1
@@ -23,7 +23,7 @@
 .Sh SYNOPSIS
 .Nm tmux
 .Bk -words
-.Op Fl 28lquvV
+.Op Fl 28lCquvV
 .Op Fl c Ar shell-command
 .Op Fl f Ar file
 .Op Fl L Ar socket-name
@@ -102,6 +102,11 @@ to assume the terminal supports 256 colours.
 Like
 .Fl 2 ,
 but indicates that the terminal supports 88 colours.
+.It Fl C
+Start in control mode.
+Given twice
+.Xo ( Fl CC ) Xc
+disables echo.
 .It Fl c Ar shell-command
 Execute
 .Ar shell-command
@@ -3610,6 +3615,94 @@ option above and the
 .Xr xterm 1
 man page.
 .El
+.Sh CONTROL MODE
+.Nm
+offers a textual interface called
+.Em control mode .
+This allows applications to communicate with
+.Nm
+using a simple text-only protocol.
+.Pp
+In control mode, a client sends
+.Nm
+commands or command sequences terminated by newlines on standard input.
+Each command will produce one block of output on standard output.
+An output block consists of a
+.Em %begin
+line followed by the output (which may be empty).
+The output block ends with a
+.Em %end
+or
+.Em %error .
+.Em %begin
+and matching
+.Em %end
+or
+.Em %error
+have two arguments: an integer time (as seconds from epoch) and command number.
+For example:
+.Bd -literal -offset indent
+%begin 1363006971 2
+0: ksh* (1 panes) [80x24] [layout b25f,80x24,0,0,2] @2 (active)
+%end 1363006971 2
+.Ed
+.Pp
+In control mode,
+.Nm
+outputs notifications.
+A notification will never occur inside an output block.
+.Pp
+The following notifications are defined:
+.Pp
+.Bl -tag -width Ds
+.It Ic %exit Op Ar reason
+The
+.Nm
+client is exiting immediately, either because it is not attached to any session
+or an error occurred.
+If present,
+.Ar reason
+describes why the client exited.
+.It Ic %layout-change Ar window-id Ar window-layout
+The layout of a window with ID
+.Ar window-id
+changed.
+The new layout is
+.Ar window-layout .
+.It Ic %output Ar source-pane Ar value
+A window pane,
+.Ar source-pane ,
+produced output.
+.Ar value
+contains that output with each byte encoded as two hex digits.
+.It Ic %session-changed Ar session-id Ar name
+The client is now attached to the session with ID
+.Ar session-id ,
+which is named
+.Ar name .
+.It Ic %session-renamed Ar name
+The current session was renamed to
+.Ar name .
+.It Ic %sessions-changed
+A session was created or destroyed.
+.It Ic %unlinked-window-add Ar window-id
+The window with ID
+.Ar window-id
+was created but is not linked to the current session.
+.It Ic %window-add Ar window-id
+The window with ID
+.Ar window-id
+was linked to the current session.
+.It Ic %window-close Ar window-id
+The window with ID
+.Ar window-id
+closed.
+.It Ic %window-renamed Ar window-id Ar name
+The window with ID
+.Ar window-id
+was renamed to
+.Ar name .
+.El
 .Sh FILES
 .Bl -tag -width "/etc/tmux.confXXX" -compact
 .It Pa ~/.tmux.conf

From 7c009509676b4580065fdc6f0084a93b9758fac0 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Mon, 11 Mar 2013 15:28:34 +0000
Subject: [PATCH 17/17] Don't add prefix to %output pane id.

---
 control-notify.c | 6 +++---
 tmux.1           | 6 ++----
 2 files changed, 5 insertions(+), 7 deletions(-)

diff --git a/control-notify.c b/control-notify.c
index 6bc98b6f..90ee4ffa 100644
--- a/control-notify.c
+++ b/control-notify.c
@@ -45,7 +45,7 @@ control_notify_input(struct client *c, struct window_pane *wp,
 	 */
 	if (winlink_find_by_window(&c->session->windows, wp->window) != NULL) {
 		message = evbuffer_new();
-		evbuffer_add_printf(message, "%%output %%%u ", wp->id);
+		evbuffer_add_printf(message, "%%output %u ", wp->id);
 		for (i = 0; i < len; i++)
 			evbuffer_add_printf(message, "%02hhx", buf[i]);
 		control_write_buffer(c, message);
@@ -141,7 +141,7 @@ control_notify_window_renamed(struct window *w)
 			continue;
 		s = c->session;
 
-                control_write(c, "%%window-renamed %u %s", w->id, w->name);
+		control_write(c, "%%window-renamed %u %s", w->id, w->name);
 	}
 }
 
@@ -154,7 +154,7 @@ control_notify_attached_session_changed(struct client *c)
 		return;
 	s = c->session;
 
-	control_write(c, "%%session-changed %d %s", s->id, s->name);
+	control_write(c, "%%session-changed %u %s", s->id, s->name);
 }
 
 void
diff --git a/tmux.1 b/tmux.1
index f73af3fa..519bf6fa 100644
--- a/tmux.1
+++ b/tmux.1
@@ -3669,10 +3669,8 @@ The layout of a window with ID
 changed.
 The new layout is
 .Ar window-layout .
-.It Ic %output Ar source-pane Ar value
-A window pane,
-.Ar source-pane ,
-produced output.
+.It Ic %output Ar pane-id Ar value
+A window pane produced output.
 .Ar value
 contains that output with each byte encoded as two hex digits.
 .It Ic %session-changed Ar session-id Ar name