Replace the notification system with events. Events can carry a payload of

additional payload (to reduce problems with lifetime of objects) and are
delivered to one or more event sinks. This is more powerful and reduces the
complex dependencies between control mode and hooks. Events are now used for
hooks, control mode notifications and for monitors (set-hook -B).

wait-for can now wait for an event to fire (-E flag, with -F to for filter),
with -v to print the payload, as well as listing (-l) waiting clients on an
event and forcing one to wake (-w).

A few additional hooks are also now available (pane-created, pane-resized, etc)
and some of the existing ones have additional format variables available.

Makefile

@@ -1,4 +1,4 @@
-# $OpenBSD$
+# $OpenBSD: Makefile,v 1.120 2026/07/10 13:38:45 nicm Exp $
 
 PROG=	tmux
 SRCS=	alerts.c \
@@ -76,6 +76,8 @@ SRCS=	alerts.c \
 	control-notify.c \
 	control.c \
 	environ.c \
+	events.c \
+	events-payload.c \
 	file.c \
 	format.c \
 	fuzzy.c \
@@ -83,6 +85,7 @@ SRCS=	alerts.c \
 	grid-reader.c \
 	grid-view.c \
 	grid.c \
+	hooks.c \
 	hyperlinks.c \
 	input-keys.c \
 	input.c \
@@ -97,7 +100,6 @@ SRCS=	alerts.c \
 	mode-tree.c \
 	monitor.c \
 	names.c \
-	notify.c \
 	options-table.c \
 	options.c \
 	paste.c \

alerts.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: alerts.c,v 1.35 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -206,7 +206,7 @@ alerts_check_bell(struct window *w)
 		}
 		if (!alerts_action_applies(wl, "bell-action"))
 			continue;
-		notify_winlink("alert-bell", wl);
+		events_fire_winlink("alert-bell", wl);
 
 		if (s->flags & SESSION_ALERTED)
 			continue;
@@ -242,7 +242,7 @@ alerts_check_activity(struct window *w)
 		}
 		if (!alerts_action_applies(wl, "activity-action"))
 			continue;
-		notify_winlink("alert-activity", wl);
+		events_fire_winlink("alert-activity", wl);
 
 		if (s->flags & SESSION_ALERTED)
 			continue;
@@ -278,7 +278,7 @@ alerts_check_silence(struct window *w)
 		}
 		if (!alerts_action_applies(wl, "silence-action"))
 			continue;
-		notify_winlink("alert-silence", wl);
+		events_fire_winlink("alert-silence", wl);
 
 		if (s->flags & SESSION_ALERTED)
 			continue;

arguments.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: arguments.c,v 1.66 2026/06/26 09:54:56 nicm Exp $ */
 
 /*
  * Copyright (c) 2010 Nicholas Marriott <nicholas.marriott@gmail.com>

attributes.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: attributes.c,v 1.13 2026/07/02 08:51:05 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Joshua Elsasser <josh@elsasser.org>

cfg.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cfg.c,v 1.89 2026/06/25 11:39:11 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

client.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: client.c,v 1.165 2025/04/25 12:25:32 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-attach-session.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-attach-session.c,v 1.91 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -163,7 +163,7 @@ cmd_attach_session(struct cmdq_item *item, const char *tflag, int dflag,
 
 		if (~c->flags & CLIENT_CONTROL)
 			proc_send(c->peer, MSG_READY, -1, NULL, 0);
-		notify_client("client-attached", c);
+		events_fire_client("client-attached", c);
 		c->flags |= CLIENT_ATTACHED;
 	}
 

cmd-bind-key.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-bind-key.c,v 1.47 2025/04/09 07:03:04 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-break-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-break-pane.c,v 1.72 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -80,7 +80,7 @@ cmd_break_pane_float(struct cmdq_item *item, struct args *args,
 		window_set_active_pane(w, wp, 1);
 	layout_fix_offsets(w);
 	layout_fix_panes(w, NULL);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 
 	return (CMD_RETURN_NORMAL);
@@ -99,7 +99,7 @@ cmd_break_pane_exec(struct cmd *self, struct cmdq_item *item)
 	struct session		*dst_s = target->s;
 	struct window_pane	*wp = source->wp;
 	struct window		*w = wl->window;
-	char			*newname, *cause, *cp;
+	char			*cause, *cp;
 	int			 idx = target->idx, before;
 	const char		*template, *name = args_get(args, 'n');
 
@@ -151,6 +151,7 @@ cmd_break_pane_exec(struct cmd *self, struct cmdq_item *item)
 	layout_close_pane(wp);
 
 	w = wp->window = window_create(w->sx, w->sy, w->xpixel, w->ypixel);
+	window_add_ref(w, __func__);
 	options_set_parent(wp->options, w->options);
 	wp->flags |= (PANE_STYLECHANGED|PANE_THEMECHANGED);
 	TAILQ_INSERT_HEAD(&w->panes, wp, entry);
@@ -158,12 +159,11 @@ cmd_break_pane_exec(struct cmd *self, struct cmdq_item *item)
 	w->active = wp;
 	w->latest = tc;
 
-	if (name == NULL) {
+	free(w->name);
-		newname = default_window_name(w);
+	if (name == NULL)
-		window_set_name(w, newname, 0);
+		w->name = default_window_name(w);
-		free(newname);
+	else {
-	} else {
+		w->name = clean_name(name, 0);
-		window_set_name(w, name, 0);
 		options_set_number(w->options, "automatic-rename", 0);
 	}
 
@@ -174,6 +174,7 @@ cmd_break_pane_exec(struct cmd *self, struct cmdq_item *item)
 	if (idx == -1)
 		idx = -1 - options_get_number(dst_s->options, "base-index");
 	wl = session_attach(dst_s, w, idx, &cause); /* can't fail */
+	window_remove_ref(w, __func__);
 	if (!args_has(args, 'd')) {
 		session_select(dst_s, wl->idx);
 		cmd_find_from_session(current, dst_s, 0);

cmd-capture-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-capture-pane.c,v 1.67 2026/07/02 10:34:14 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Jonathan Alvarado <radobobo@users.sourceforge.net>

cmd-choose-tree.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-choose-tree.c,v 1.57 2026/06/26 14:40:30 nicm Exp $ */
 
 /*
  * Copyright (c) 2012 Thomas Adam <thomas@xteddy.org>

cmd-command-prompt.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-command-prompt.c,v 1.75 2026/06/25 11:39:11 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-confirm-before.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-confirm-before.c,v 1.61 2026/06/24 10:55:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>

cmd-copy-mode.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-copy-mode.c,v 1.53 2026/07/08 08:07:42 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-detach-client.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-detach-client.c,v 1.39 2026/05/22 15:22:43 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-display-menu.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-display-menu.c,v 1.51 2026/07/07 09:45:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-display-message.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-display-message.c,v 1.65 2026/02/23 08:46:57 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>

cmd-display-panes.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-display-panes.c,v 1.56 2026/06/25 16:32:42 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-find-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-find-window.c,v 1.56 2023/12/27 20:42:01 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-find.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-find.c,v 1.86 2026/07/02 08:47:25 nicm Exp $ */
 
 /*
  * Copyright (c) 2015 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-has-session.c

@@ -1,46 +0,0 @@
-/* $OpenBSD$ */
-
-/*
- * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
- *
- * 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 "tmux.h"
-
-/*
- * Cause client to report an error and exit with 1 if session doesn't exist.
- */
-
-enum cmd_retval	 cmd_has_session_exec(struct cmd *, struct cmd_q *);
-
-const struct cmd_entry cmd_has_session_entry = {
-	"has-session", "has",
-	"t:", 0, 0,
-	CMD_TARGET_SESSION_USAGE,
-	0,
-	cmd_has_session_exec
-};
-
-enum cmd_retval
-cmd_has_session_exec(struct cmd *self, struct cmd_q *cmdq)
-{
-	struct args	*args = self->args;
-
-	if (cmd_find_session(cmdq, args_get(args, 't'), 0) == NULL)
-		return (CMD_RETURN_ERROR);
-
-	return (CMD_RETURN_NORMAL);
-}

cmd-if-shell.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-if-shell.c,v 1.86 2025/08/01 09:05:51 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>

cmd-join-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-join-pane.c,v 1.69 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 George Nachman <tmux@georgester.com>
@@ -187,7 +187,7 @@ cmd_join_pane_place(struct cmdq_item *item, struct winlink *wl,
 		lc->g.yoff = yoff;
 		layout_fix_panes(w, NULL);
 	}
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 
 	return (CMD_RETURN_NORMAL);
@@ -257,7 +257,7 @@ cmd_join_pane_move(struct cmdq_item *item, struct args *args,
 		lc->g.xoff = xoff;
 		lc->g.yoff = yoff;
 		layout_fix_panes(w, NULL);
-		notify_window("window-layout-changed", w);
+		events_fire_window("window-layout-changed", w);
 		server_redraw_window(w);
 	}
 
@@ -359,7 +359,7 @@ cmd_join_pane_zindex(struct cmdq_item *item, struct winlink *wl,
 	else
 		TAILQ_INSERT_TAIL(&w->z_index, wp, zentry);
 
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 
 	return (CMD_RETURN_NORMAL);
@@ -398,7 +398,7 @@ cmd_join_pane_tile(struct cmdq_item *item, struct args *args, struct window *w,
 		window_set_active_pane(w, wp, 1);
 	layout_fix_offsets(w);
 	layout_fix_panes(w, NULL);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 
 	return (CMD_RETURN_NORMAL);
@@ -502,8 +502,8 @@ cmd_join_pane_exec(struct cmd *self, struct cmdq_item *item)
 	if (window_count_panes(src_w, 1) == 0)
 		server_kill_window(src_w, 1);
 	else
-		notify_window("window-layout-changed", src_w);
+		events_fire_window("window-layout-changed", src_w);
-	notify_window("window-layout-changed", dst_w);
+	events_fire_window("window-layout-changed", dst_w);
 
 	return (CMD_RETURN_NORMAL);
 }

cmd-kill-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-kill-pane.c,v 1.34 2026/06/09 21:22:22 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-kill-server.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-kill-server.c,v 1.20 2021/08/21 10:22:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-kill-session.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-kill-session.c,v 1.31 2026/06/09 12:57:40 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-kill-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-kill-window.c,v 1.30 2026/06/09 12:57:40 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-buffers.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-buffers.c,v 1.41 2026/02/27 08:25:12 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-clients.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-clients.c,v 1.42 2026/02/27 08:25:12 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-commands.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-commands.c,v 1.15 2026/02/24 08:22:13 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-keys.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-keys.c,v 1.78 2026/07/01 13:12:17 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-panes.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-panes.c,v 1.40 2026/06/01 14:01:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-sessions.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-sessions.c,v 1.36 2026/02/27 08:25:12 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list-windows.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-list-windows.c,v 1.50 2026/02/27 08:25:12 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-list.c

@@ -1,103 +0,0 @@
-/* $OpenBSD$ */
-
-/*
- * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@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"
-
-static u_int cmd_list_next_group = 1;
-
-struct cmd_list *
-cmd_list_new(void)
-{
-	struct cmd_list	*cmdlist;
-
-	cmdlist = xcalloc(1, sizeof *cmdlist);
-	cmdlist->references = 1;
-	cmdlist->group = cmd_list_next_group++;
-	TAILQ_INIT(&cmdlist->list);
-	return (cmdlist);
-}
-
-void
-cmd_list_append(struct cmd_list *cmdlist, struct cmd *cmd)
-{
-	cmd->group = cmdlist->group;
-	TAILQ_INSERT_TAIL(&cmdlist->list, cmd, qentry);
-}
-
-void
-cmd_list_move(struct cmd_list *cmdlist, struct cmd_list *from)
-{
-	struct cmd	*cmd, *cmd1;
-
-	TAILQ_FOREACH_SAFE(cmd, &from->list, qentry, cmd1) {
-		TAILQ_REMOVE(&from->list, cmd, qentry);
-		TAILQ_INSERT_TAIL(&cmdlist->list, cmd, qentry);
-	}
-	cmdlist->group = cmd_list_next_group++;
-}
-
-void
-cmd_list_free(struct cmd_list *cmdlist)
-{
-	struct cmd	*cmd, *cmd1;
-
-	if (--cmdlist->references != 0)
-		return;
-
-	TAILQ_FOREACH_SAFE(cmd, &cmdlist->list, qentry, cmd1) {
-		TAILQ_REMOVE(&cmdlist->list, cmd, qentry);
-		cmd_free(cmd);
-	}
-
-	free(cmdlist);
-}
-
-char *
-cmd_list_print(struct cmd_list *cmdlist, int escaped)
-{
-	struct cmd	*cmd;
-	char		*buf, *this;
-	size_t		 len;
-
-	len = 1;
-	buf = xcalloc(1, len);
-
-	TAILQ_FOREACH(cmd, &cmdlist->list, qentry) {
-		this = cmd_print(cmd);
-
-		len += strlen(this) + 4;
-		buf = xrealloc(buf, len);
-
-		strlcat(buf, this, len);
-		if (TAILQ_NEXT(cmd, qentry) != NULL) {
-			if (escaped)
-				strlcat(buf, " \\; ", len);
-			else
-				strlcat(buf, " ; ", len);
-		}
-
-		free(this);
-	}
-
-	return (buf);
-}

cmd-load-buffer.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-load-buffer.c,v 1.66 2025/10/28 07:32:26 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>

cmd-lock-server.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-lock-server.c,v 1.31 2021/08/21 10:22:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-move-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-move-window.c,v 1.34 2021/08/21 10:22:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-new-session.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-new-session.c,v 1.152 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -325,7 +325,7 @@ cmd_new_session_exec(struct cmd *self, struct cmdq_item *item)
 		session_group_synchronize_to(s);
 		session_select(s, RB_MIN(winlinks, &s->windows)->idx);
 	}
-	notify_session("session-created", s);
+	events_fire_session("session-created", s);
 
 	/*
 	 * Set the client to the new session. If a command client exists, it is

cmd-new-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-new-window.c,v 1.103 2026/07/08 08:07:42 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-parse.y

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-parse.y,v 1.58 2026/04/27 12:31:11 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-paste-buffer.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-paste-buffer.c,v 1.44 2026/03/04 07:19:32 tb Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-pipe-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-pipe-pane.c,v 1.63 2026/04/28 08:47:55 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-queue.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-queue.c,v 1.120 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2013 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -351,74 +351,53 @@ cmdq_insert_after(struct cmdq_item *after, struct cmdq_item *item)
 
 /* Insert a hook. */
 void
-cmdq_insert_hook(struct session *s, struct cmdq_item *item,
+cmdq_insert_hook(__unused struct session *s, struct cmdq_item *item,
     struct cmd_find_state *current, const char *fmt, ...)
 {
-	struct cmdq_state		*state = item->state;
 	struct cmd			*cmd = item->cmd;
 	struct args			*args = cmd_get_args(cmd);
 	struct args_entry		*ae;
 	struct args_value		*av;
-	struct options			*oo;
+	struct event_payload		*ep;
 	va_list				 ap;
 	char				*name, tmp[32], flag, *arguments;
 	u_int				 i;
 	const char			*value;
-	struct cmdq_item		*new_item;
-	struct cmdq_state		*new_state;
-	struct options_entry		*o;
-	struct options_array_item	*a;
-	struct cmd_list			*cmdlist;
 
 	if (item->state->flags & CMDQ_STATE_NOHOOKS)
 		return;
-	if (s == NULL)
-		oo = global_s_options;
-	else
-		oo = s->options;
 
 	va_start(ap, fmt);
 	xvasprintf(&name, fmt, ap);
 	va_end(ap);
 
-	o = options_get(oo, name);
+	ep = event_payload_create();
-	if (o == NULL) {
+	if (current != NULL)
-		free(name);
+		event_payload_set_target(ep, current);
-		return;
+	event_payload_set_pointer(ep, "_cmdq_item", item, NULL, NULL);
-	}
-	log_debug("running hook %s (parent %p)", name, item);
-
-	/*
-	 * The hooks get a new state because they should not update the current
-	 * target or formats for any subsequent commands.
-	 */
-	new_state = cmdq_new_state(current, &state->event, CMDQ_STATE_NOHOOKS);
-	cmdq_add_format(new_state, "hook", "%s", name);
 
 	arguments = args_print(args);
-	cmdq_add_format(new_state, "hook_arguments", "%s", arguments);
+	event_payload_set_string(ep, "arguments", "%s", arguments);
 	free(arguments);
 
 	for (i = 0; i < args_count(args); i++) {
-		xsnprintf(tmp, sizeof tmp, "hook_argument_%d", i);
+		xsnprintf(tmp, sizeof tmp, "argument_%u", i);
-		cmdq_add_format(new_state, tmp, "%s", args_string(args, i));
+		event_payload_set_string(ep, tmp, "%s", args_string(args, i));
 	}
 	flag = args_first(args, &ae);
 	while (flag != 0) {
 		value = args_get(args, flag);
-		if (value == NULL) {
+		xsnprintf(tmp, sizeof tmp, "flag_%c", flag);
-			xsnprintf(tmp, sizeof tmp, "hook_flag_%c", flag);
+		if (value == NULL)
-			cmdq_add_format(new_state, tmp, "1");
+			event_payload_set_string(ep, tmp, "1");
-		} else {
+		else
-			xsnprintf(tmp, sizeof tmp, "hook_flag_%c", flag);
+			event_payload_set_string(ep, tmp, "%s", value);
-			cmdq_add_format(new_state, tmp, "%s", value);
-		}
 
 		i = 0;
 		av = args_first_value(args, flag);
 		while (av != NULL) {
-			xsnprintf(tmp, sizeof tmp, "hook_flag_%c_%d", flag, i);
+			xsnprintf(tmp, sizeof tmp, "flag_%c_%u", flag, i);
-			cmdq_add_format(new_state, tmp, "%s", av->string);
+			event_payload_set_string(ep, tmp, "%s", av->string);
 			i++;
 			av = args_next_value(av);
 		}
@@ -426,20 +405,7 @@ cmdq_insert_hook(struct session *s, struct cmdq_item *item,
 		flag = args_next(&ae);
 	}
 
-	a = options_array_first(o);
+	events_fire(name, ep);
-	while (a != NULL) {
-		cmdlist = options_array_item_value(a)->cmdlist;
-		if (cmdlist != NULL) {
-			new_item = cmdq_get_command(cmdlist, new_state);
-			if (item != NULL)
-				item = cmdq_insert_after(item, new_item);
-			else
-				item = cmdq_append(NULL, new_item);
-		}
-		a = options_array_next(a);
-	}
-
-	cmdq_free_state(new_state);
 	free(name);
 }
 

cmd-refresh-client.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-refresh-client.c,v 1.54 2026/07/05 08:24:00 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-rename-session.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-rename-session.c,v 1.39 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -49,6 +49,8 @@ cmd_rename_session_exec(struct cmd *self, struct cmdq_item *item)
 	struct args		*args = cmd_get_args(self);
 	struct cmd_find_state	*target = cmdq_get_target(item);
 	struct session		*s = target->s;
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
 	char			*newname, *tmp;
 
 	tmp = format_single_from_target(item, args_string(args, 0));
@@ -69,13 +71,20 @@ cmd_rename_session_exec(struct cmd *self, struct cmdq_item *item)
 		return (CMD_RETURN_ERROR);
 	}
 
+	ep = event_payload_create();
+	cmd_find_from_session(&fs, s, 0);
+	event_payload_set_target(ep, &fs);
+	event_payload_set_session(ep, "session", s);
+	event_payload_set_string(ep, "old_name", "%s", s->name);
+	event_payload_set_string(ep, "new_name", "%s", newname);
+
 	RB_REMOVE(sessions, &sessions, s);
 	free(s->name);
 	s->name = newname;
 	RB_INSERT(sessions, &sessions, s);
 
 	server_status_session(s);
-	notify_session("session-renamed", s);
+	events_fire("session-renamed", ep);
 
 	return (CMD_RETURN_NORMAL);
 }

cmd-rename-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-rename-window.c,v 1.30 2026/06/29 18:17:28 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-resize-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-resize-pane.c,v 1.67 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -182,7 +182,7 @@ cmd_resize_pane_exec(struct cmd *self, struct cmdq_item *item)
 	if (lc->parent != NULL)
 		layout_fix_offsets(w);
 	layout_fix_panes(w, NULL);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 
 	return (CMD_RETURN_NORMAL);

cmd-resize-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-resize-window.c,v 1.10 2023/06/30 13:19:32 nicm Exp $ */
 
 /*
  * Copyright (c) 2018 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-respawn-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-respawn-pane.c,v 1.40 2026/07/03 16:09:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-respawn-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-respawn-window.c,v 1.51 2026/07/03 16:09:49 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-rotate-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-rotate-window.c,v 1.34 2026/06/22 08:47:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-run-shell.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-run-shell.c,v 1.91 2026/06/01 08:27:37 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>

cmd-save-buffer.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-save-buffer.c,v 1.57 2025/10/28 07:32:26 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Tiago Cunha <me@tiagocunha.org>

cmd-select-layout.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-select-layout.c,v 1.43 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -139,7 +139,7 @@ changed:
 	free(oldlayout);
 	recalculate_sizes();
 	server_redraw_window(w);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	return (CMD_RETURN_NORMAL);
 
 error:

cmd-select-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-select-pane.c,v 1.76 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -80,6 +80,69 @@ cmd_select_pane_redraw(struct window *w)
 	}
 }
 
+static enum cmd_retval
+cmd_select_pane_marked_pane(struct cmd *self, struct cmdq_item *item)
+{
+	struct args		*args = cmd_get_args(self);
+	struct cmd_find_state	*target = cmdq_get_target(item);
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+	struct winlink		*wl = target->wl;
+	struct window_pane	*wp = target->wp, *lwp = NULL, *mwp;
+	struct session		*s = target->s;
+
+	if (args_has(args, 'm') && !window_pane_is_visible(wp))
+		return (CMD_RETURN_NORMAL);
+	if (server_check_marked())
+		lwp = marked_pane.wp;
+
+	if (args_has(args, 'M') || server_is_marked(s, wl, wp))
+		server_clear_marked();
+	else
+		server_set_marked(s, wl, wp);
+	mwp = marked_pane.wp;
+
+	ep = event_payload_create();
+	if (mwp != NULL)
+		cmd_find_from_pane(&fs, mwp, 0);
+	else if (lwp != NULL)
+		cmd_find_from_pane(&fs, lwp, 0);
+	else
+		cmd_find_from_pane(&fs, wp, 0);
+	event_payload_set_target(ep, &fs);
+	if (mwp != NULL) {
+		event_payload_set_pane(ep, "pane", mwp);
+		event_payload_set_pane(ep, "new_pane", mwp);
+		event_payload_set_window(ep, "window", mwp->window);
+	} else if (lwp != NULL) {
+		event_payload_set_pane(ep, "pane", lwp);
+		event_payload_set_window(ep, "window", lwp->window);
+	} else {
+		event_payload_set_pane(ep, "pane", wp);
+		event_payload_set_window(ep, "window", wp->window);
+	}
+	if (lwp != NULL)
+		event_payload_set_pane(ep, "old_pane", lwp);
+	event_payload_set_int(ep, "marked", mwp != NULL);
+	events_fire("marked-pane-changed", ep);
+
+	if (lwp != NULL) {
+		lwp->flags |= (PANE_REDRAW|PANE_STYLECHANGED|PANE_THEMECHANGED);
+		server_redraw_window_borders(lwp->window);
+		server_status_window(lwp->window);
+	}
+	if (mwp != NULL) {
+		mwp->flags |= (PANE_REDRAW|PANE_STYLECHANGED|PANE_THEMECHANGED);
+		server_redraw_window_borders(mwp->window);
+		server_status_window(mwp->window);
+	}
+	if (window_pane_is_floating(wp)) {
+		window_redraw_active_switch(wp->window, wp);
+		window_set_active_pane(wp->window, wp, 1);
+	}
+	return (CMD_RETURN_NORMAL);
+}
+
 static enum cmd_retval
 cmd_select_pane_exec(struct cmd *self, struct cmdq_item *item)
 {
@@ -88,10 +151,12 @@ cmd_select_pane_exec(struct cmd *self, struct cmdq_item *item)
 	struct cmd_find_state	*current = cmdq_get_current(item);
 	struct cmd_find_state	*target = cmdq_get_target(item);
 	struct client		*c = cmdq_get_client(item);
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
 	struct winlink		*wl = target->wl;
 	struct window		*w = wl->window;
 	struct session		*s = target->s;
-	struct window_pane	*wp = target->wp, *activewp, *lastwp, *markedwp;
+	struct window_pane	*wp = target->wp, *activewp, *lastwp;
 	struct options		*oo = wp->options;
 	char			*title;
 	const char		*style;
@@ -134,38 +199,8 @@ cmd_select_pane_exec(struct cmd *self, struct cmdq_item *item)
 		return (CMD_RETURN_NORMAL);
 	}
 
-	if (args_has(args, 'm') || args_has(args, 'M')) {
+	if (args_has(args, 'm') || args_has(args, 'M'))
-		if (args_has(args, 'm') && !window_pane_is_visible(wp))
+		return (cmd_select_pane_marked_pane(self, item));
-			return (CMD_RETURN_NORMAL);
-		if (server_check_marked())
-			lastwp = marked_pane.wp;
-		else
-			lastwp = NULL;
-
-		if (args_has(args, 'M') || server_is_marked(s, wl, wp))
-			server_clear_marked();
-		else
-			server_set_marked(s, wl, wp);
-		markedwp = marked_pane.wp;
-
-		if (lastwp != NULL) {
-			lastwp->flags |= (PANE_REDRAW|PANE_STYLECHANGED|
-			    PANE_THEMECHANGED);
-			server_redraw_window_borders(lastwp->window);
-			server_status_window(lastwp->window);
-		}
-		if (markedwp != NULL) {
-			markedwp->flags |= (PANE_REDRAW|PANE_STYLECHANGED|
-			    PANE_THEMECHANGED);
-			server_redraw_window_borders(markedwp->window);
-			server_status_window(markedwp->window);
-		}
-		if (window_pane_is_floating(wp)) {
-			window_redraw_active_switch(w, wp);
-			window_set_active_pane(w, wp, 1);
-		}
-		return (CMD_RETURN_NORMAL);
-	}
 
 	style = args_get(args, 'P');
 	if (style != NULL) {
@@ -218,7 +253,13 @@ cmd_select_pane_exec(struct cmd *self, struct cmdq_item *item)
 	if (args_has(args, 'T')) {
 		title = format_single_from_target(item, args_get(args, 'T'));
 		if (screen_set_title(&wp->base, title, 0)) {
-			notify_pane("pane-title-changed", wp);
+			ep = event_payload_create();
+			cmd_find_from_pane(&fs, wp, 0);
+			event_payload_set_target(ep, &fs);
+			event_payload_set_pane(ep, "pane", wp);
+			event_payload_set_window(ep, "window", wp->window);
+			event_payload_set_string(ep, "new_title", "%s", title);
+			events_fire("pane-title-changed", ep);
 			server_redraw_window_borders(wp->window);
 			server_status_window(wp->window);
 		}

cmd-select-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-select-window.c,v 1.30 2021/08/21 10:22:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-send-keys.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-send-keys.c,v 1.81 2026/06/11 19:13:34 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-send-prefix.c

@@ -1,57 +0,0 @@
-/* $OpenBSD$ */
-
-/*
- * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
- *
- * 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 "tmux.h"
-
-/*
- * Send prefix key as a key.
- */
-
-enum cmd_retval	 cmd_send_prefix_exec(struct cmd *, struct cmd_ctx *);
-
-const struct cmd_entry cmd_send_prefix_entry = {
-	"send-prefix", NULL,
-	"2t:", 0, 0,
-	"[-2] " CMD_TARGET_PANE_USAGE,
-	0,
-	NULL,
-	NULL,
-	cmd_send_prefix_exec
-};
-
-enum cmd_retval
-cmd_send_prefix_exec(struct cmd *self, struct cmd_ctx *ctx)
-{
-	struct args		*args = self->args;
-	struct session		*s;
-	struct window_pane	*wp;
-	int			 key;
-
-	if (cmd_find_pane(ctx, args_get(args, 't'), &s, &wp) == NULL)
-		return (CMD_RETURN_ERROR);
-
-	if (args_has(args, '2'))
-		key = options_get_number(&s->options, "prefix2");
-	else
-		key = options_get_number(&s->options, "prefix");
-	window_pane_key(wp, s, key);
-
-	return (CMD_RETURN_NORMAL);
-}

cmd-server-access.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-server-access.c,v 1.6 2026/06/09 12:58:40 nicm Exp $ */
 
 /*
  * Copyright (c) 2021 Dallas Lyons <dallasdlyons@gmail.com>

cmd-set-buffer.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-set-buffer.c,v 1.37 2026/02/15 17:43:26 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-set-environment.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-set-environment.c,v 1.29 2025/04/09 06:27:43 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-set-option.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-set-option.c,v 1.145 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -31,6 +31,8 @@ static enum args_parse_type	cmd_set_option_args_parse(struct args *,
 				    u_int, char **);
 static enum cmd_retval		cmd_set_option_exec(struct cmd *,
 				    struct cmdq_item *);
+static enum cmd_retval		cmd_set_hook_event_exec(struct cmd *,
+				    struct cmdq_item *);
 static enum cmd_retval		cmd_set_hook_monitor_exec(struct cmdq_item *,
 				    struct args *, int);
 
@@ -64,8 +66,8 @@ const struct cmd_entry cmd_set_hook_entry = {
 	.name = "set-hook",
 	.alias = NULL,
 
-	.args = { "agpRt:uB:w", 0, 2, cmd_set_option_args_parse },
+	.args = { "agpERt:uB:w", 0, 2, cmd_set_option_args_parse },
-	.usage = "[-agpRuw] [-B name:what:format] " CMD_TARGET_PANE_USAGE " "
+	.usage = "[-agpERuw] [-B name:what:format] " CMD_TARGET_PANE_USAGE " "
 		 "[hook] [command]",
 
 	.target = { 't', CMD_FIND_PANE, CMD_FIND_CANFAIL },
@@ -85,12 +87,58 @@ cmd_set_option_args_parse(struct args *args, u_int idx,
 	return (ARGS_PARSE_STRING);
 }
 
+static enum cmd_retval
+cmd_set_hook_event_exec(struct cmd *self, struct cmdq_item *item)
+{
+	struct args		*args = cmd_get_args(self);
+	struct cmd_find_state	*target = cmdq_get_target(item);
+	struct event_payload	*ep;
+	struct client		*c;
+	char			*argument;
+
+	if (args_count(args) == 0) {
+		cmdq_error(item, "missing argument");
+		return (CMD_RETURN_ERROR);
+	}
+	if (args_count(args) != 1) {
+		cmdq_error(item, "too many arguments");
+		return (CMD_RETURN_ERROR);
+	}
+
+	argument = format_single_from_target(item, args_string(args, 0));
+	if (*argument != '@') {
+		cmdq_error(item, "event name must start with @");
+		free(argument);
+		return (CMD_RETURN_ERROR);
+	}
+
+	ep = event_payload_create();
+	event_payload_set_target(ep, target);
+	c = cmdq_get_client(item);
+	if (c != NULL)
+		event_payload_set_client(ep, "client", c);
+	if (target->s != NULL)
+		event_payload_set_session(ep, "session", target->s);
+	if (target->w != NULL)
+		event_payload_set_window(ep, "window", target->w);
+	if (target->wl != NULL)
+		event_payload_set_int(ep, "window_index", target->wl->idx);
+	else if (target->idx != -1)
+		event_payload_set_int(ep, "window_index", target->idx);
+	if (target->wp != NULL)
+		event_payload_set_pane(ep, "pane", target->wp);
+	events_fire(argument, ep);
+	free(argument);
+	return (CMD_RETURN_NORMAL);
+}
+
 static enum cmd_retval
 cmd_set_hook_monitor_exec(struct cmdq_item *item, struct args *args, int window)
 {
 	struct cmd_find_state	*target = cmdq_get_target(item), fs;
 	struct options		*oo;
 	struct options_entry	*o;
+	struct session		*s = NULL;
 	char			*cause = NULL, *name = NULL, *format = NULL;
 	char			*expanded = NULL, *newvalue = NULL;
 	const char		*value, *old;
@@ -130,7 +178,7 @@ cmd_set_hook_monitor_exec(struct cmdq_item *item, struct args *args, int window)
 	cmd_find_copy_state(&fs, target);
 
 	if (args_has(args, 'u')) {
-		notify_monitor_remove(oo, name);
+		hooks_monitor_remove(oo, name);
 		goto out;
 	}
 
@@ -152,7 +200,11 @@ cmd_set_hook_monitor_exec(struct cmdq_item *item, struct args *args, int window)
 		}
 	}
 
-	notify_monitor_add(item, oo, name, type, id, format, &fs, target->s);
+	if (oo != global_options &&
+	    oo != global_s_options &&
+	    oo != global_w_options)
+		s = target->s;
+	hooks_monitor_add(item, oo, name, type, id, format, &fs, s);
 
 out:
 	free(newvalue);
@@ -185,6 +237,8 @@ cmd_set_option_exec(struct cmd *self, struct cmdq_item *item)
 	int				 scope;
 
 	window = (cmd_get_entry(self) == &cmd_set_window_option_entry);
+	if (cmd_get_entry(self) == &cmd_set_hook_entry && args_has(args, 'E'))
+		return (cmd_set_hook_event_exec(self, item));
 	if (cmd_get_entry(self) == &cmd_set_hook_entry && args_has(args, 'B'))
 		return (cmd_set_hook_monitor_exec(item, args, window));
 	if (args_count(args) == 0) {
@@ -197,7 +251,7 @@ cmd_set_option_exec(struct cmd *self, struct cmdq_item *item)
 
 	/* If set-hook -R, fire the hook straight away. */
 	if (cmd_get_entry(self) == &cmd_set_hook_entry && args_has(args, 'R')) {
-		notify_hook(item, argument);
+		hooks_run(item, argument);
 		free(argument);
 		return (CMD_RETURN_NORMAL);
 	}
@@ -289,6 +343,8 @@ cmd_set_option_exec(struct cmd *self, struct cmdq_item *item)
 			goto fail;
 		}
 		options_set_string(oo, name, append, "%s", value);
+		if (cmd_get_entry(self) == &cmd_set_hook_entry)
+			hooks_add_event(name);
 	} else if (array_key == NULL && !options_is_array(parent)) {
 		error = options_from_string(oo, options_table_entry(parent),
 		    options_table_entry(parent)->name, value,

cmd-show-buffer.c

@@ -1,112 +0,0 @@
-/* $OpenBSD$ */
-
-/*
- * Copyright (c) 2007 Nicholas Marriott <nicm@users.sourceforge.net>
- *
- * 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 <vis.h>
-
-#include "tmux.h"
-
-/*
- * Show a paste buffer.
- */
-
-enum cmd_retval	 cmd_show_buffer_exec(struct cmd *, struct cmd_ctx *);
-
-const struct cmd_entry cmd_show_buffer_entry = {
-	"show-buffer", "showb",
-	"b:", 0, 0,
-	CMD_BUFFER_USAGE,
-	0,
-	NULL,
-	NULL,
-	cmd_show_buffer_exec
-};
-
-enum cmd_retval
-cmd_show_buffer_exec(struct cmd *self, struct cmd_ctx *ctx)
-{
-	struct args		*args = self->args;
-	struct session		*s;
-	struct paste_buffer	*pb;
-	int			 buffer;
-	char			*in, *buf, *ptr, *cause;
-	size_t			 size, len;
-	u_int			 width;
-
-	if ((s = cmd_find_session(ctx, NULL, 0)) == NULL)
-		return (CMD_RETURN_ERROR);
-
-	if (!args_has(args, 'b')) {
-		if ((pb = paste_get_top(&global_buffers)) == NULL) {
-			ctx->error(ctx, "no buffers");
-			return (CMD_RETURN_ERROR);
-		}
-	} else {
-		buffer = args_strtonum(args, 'b', 0, INT_MAX, &cause);
-		if (cause != NULL) {
-			ctx->error(ctx, "buffer %s", cause);
-			free(cause);
-			return (CMD_RETURN_ERROR);
-		}
-
-		pb = paste_get_index(&global_buffers, buffer);
-		if (pb == NULL) {
-			ctx->error(ctx, "no buffer %d", buffer);
-			return (CMD_RETURN_ERROR);
-		}
-	}
-
-	size = pb->size;
-	if (size > SIZE_MAX / 4 - 1)
-		size = SIZE_MAX / 4 - 1;
-	in = xmalloc(size * 4 + 1);
-	strvisx(in, pb->data, size, VIS_OCTAL|VIS_TAB);
-
-	width = s->sx;
-	if (ctx->cmdclient != NULL)
-		width = ctx->cmdclient->tty.sx;
-
-	buf = xmalloc(width + 1);
-	len = 0;
-
-	ptr = in;
-	do {
-		buf[len++] = *ptr++;
-
-		if (len == width || buf[len - 1] == '\n') {
-			if (buf[len - 1] == '\n')
-				len--;
-			buf[len] = '\0';
-
-			ctx->print(ctx, "%s", buf);
-			len = 0;
-		}
-	} while (*ptr != '\0');
-
-	if (len != 0) {
-		buf[len] = '\0';
-		ctx->print(ctx, "%s", buf);
-	}
-	free(buf);
-
-	free(in);
-
-	return (CMD_RETURN_NORMAL);
-}

cmd-show-environment.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-show-environment.c,v 1.29 2025/04/09 06:27:43 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-show-messages.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-show-messages.c,v 1.37 2025/11/18 08:37:54 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-show-options.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-show-options.c,v 1.73 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -216,7 +216,7 @@ cmd_show_hooks_print_monitor(struct cmdq_item *item, struct options_entry *o)
 {
 	char	*value;
 
-	value = notify_monitor_to_string(o);
+	value = hooks_monitor_to_string(o);
 	if (value == NULL)
 		return;
 	cmdq_print(item, "%s", value);

cmd-show-prompt-history.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-show-prompt-history.c,v 1.5 2026/06/25 11:39:11 nicm Exp $ */
 
 /*
  * Copyright (c) 2021 Anindya Mukherjee <anindya49@hotmail.com>

cmd-source-file.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-source-file.c,v 1.62 2025/11/18 08:42:09 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Tiago Cunha <me@tiagocunha.org>

cmd-split-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-split-window.c,v 1.141 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -84,6 +84,7 @@ cmd_split_window_exec(struct cmd *self, struct cmdq_item *item)
 	struct window		*w = wl->window;
 	struct window_pane	*wp = target->wp, *new_wp = NULL;
 	struct layout_cell	*lc = NULL;
+	struct event_payload	*ep;
 	struct cmd_find_state	 fs;
 	int			 input, empty, is_floating, flags = 0;
 	const char		*template, *style, *value;
@@ -218,7 +219,13 @@ cmd_split_window_exec(struct cmd *self, struct cmdq_item *item)
 	if (args_has(args, 'T')) {
 		title = format_single_from_target(item, args_get(args, 'T'));
 		screen_set_title(&new_wp->base, title, 0);
-		notify_pane("pane-title-changed", new_wp);
+		ep = event_payload_create();
+		cmd_find_from_pane(&fs, new_wp, 0);
+		event_payload_set_target(ep, &fs);
+		event_payload_set_pane(ep, "pane", new_wp);
+		event_payload_set_window(ep, "window", new_wp->window);
+		event_payload_set_string(ep, "new_title", "%s", title);
+		events_fire("pane-title-changed", ep);
 		free(title);
 	}
 

cmd-swap-pane.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-swap-pane.c,v 1.53 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -180,9 +180,9 @@ cmd_swap_pane_exec(struct cmd *self, struct cmdq_item *item)
 	redraw_invalidate_scene(dst_w);
 	server_redraw_window(dst_w);
 
-	notify_window("window-layout-changed", src_w);
+	events_fire_window("window-layout-changed", src_w);
 	if (src_w != dst_w)
-		notify_window("window-layout-changed", dst_w);
+		events_fire_window("window-layout-changed", dst_w);
 
 out:
 	if (window_pop_zoom(src_w))

cmd-swap-window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-swap-window.c,v 1.29 2025/10/30 13:52:08 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-switch-client.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-switch-client.c,v 1.74 2026/05/22 15:22:43 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-unbind-key.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-unbind-key.c,v 1.34 2021/08/21 10:22:39 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

cmd-wait-for.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd-wait-for.c,v 1.23 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2013 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -34,8 +34,8 @@ const struct cmd_entry cmd_wait_for_entry = {
 	.name = "wait-for",
 	.alias = "wait",
 
-	.args = { "LSU", 1, 1, NULL },
+	.args = { "EF:LSUlvw:", 1, 1, NULL },
-	.usage = "[-L|-S|-U] channel",
+	.usage = "[-ELSUlv] [-F format] [-w waiter] name",
 
 	.flags = 0,
 	.exec = cmd_wait_for_exec
@@ -46,6 +46,17 @@ struct wait_item {
 	TAILQ_ENTRY(wait_item)	 entry;
 };
 
+struct wait_event_item {
+	struct cmdq_item		*item;
+	struct events_sink		*sink;
+	char				*name;
+	char				*filter;
+	int				 verbose;
+	TAILQ_ENTRY(wait_event_item)	 entry;
+};
+static TAILQ_HEAD(, wait_event_item) wait_event_items =
+    TAILQ_HEAD_INITIALIZER(wait_event_items);
+
 struct wait_channel {
 	const char	       *name;
 	int			locked;
@@ -76,9 +87,28 @@ static enum cmd_retval	cmd_wait_for_lock(struct cmdq_item *, const char *,
 			    struct wait_channel *);
 static enum cmd_retval	cmd_wait_for_unlock(struct cmdq_item *, const char *,
 			    struct wait_channel *);
+static enum cmd_retval	cmd_wait_for_event(struct cmdq_item *, const char *,
+			    struct args *);
+static void		cmd_wait_for_event_cb(const char *,
+			    struct event_payload *, void *);
+static void		cmd_wait_for_event_free(struct wait_event_item *);
+static enum cmd_retval	cmd_wait_for_event_list(struct cmdq_item *,
+			    const char *);
+static enum cmd_retval	cmd_wait_for_event_wake(struct cmdq_item *,
+			    const char *, struct args *);
+static enum cmd_retval	cmd_wait_for_list(struct cmdq_item *,
+			    struct wait_channel *);
+static enum cmd_retval	cmd_wait_for_wake(struct cmdq_item *, const char *,
+			    struct args *, struct wait_channel *);
 
 static struct wait_channel	*cmd_wait_for_add(const char *);
 static void			 cmd_wait_for_remove(struct wait_channel *);
+static void			 cmd_wait_for_remove_empty(
+				    struct wait_channel *);
+static const char		*cmd_wait_for_item_client_name(
+				    struct cmdq_item *);
+static const char		*cmd_wait_for_client_name(
+				    struct wait_event_item *);
 
 static struct wait_channel *
 cmd_wait_for_add(const char *name)
@@ -117,16 +147,53 @@ cmd_wait_for_remove(struct wait_channel *wc)
 	free(wc);
 }
 
+static void
+cmd_wait_for_remove_empty(struct wait_channel *wc)
+{
+	if (wc->locked || wc->woken)
+		return;
+	if (!TAILQ_EMPTY(&wc->waiters) || !TAILQ_EMPTY(&wc->lockers))
+		return;
+
+	log_debug("remove empty wait channel %s", wc->name);
+
+	RB_REMOVE(wait_channels, &wait_channels, wc);
+
+	free((void *)wc->name);
+	free(wc);
+}
+
+static const char *
+cmd_wait_for_item_client_name(struct cmdq_item *item)
+{
+	struct client	*c = cmdq_get_client(item);
+
+	if (c == NULL || c->name == NULL)
+		return ("");
+	return (c->name);
+}
+
+static const char *
+cmd_wait_for_client_name(struct wait_event_item *wei)
+{
+	return (cmd_wait_for_item_client_name(wei->item));
+}
+
 static enum cmd_retval
 cmd_wait_for_exec(struct cmd *self, struct cmdq_item *item)
 {
 	struct args		*args = cmd_get_args(self);
 	const char		*name = args_string(args, 0);
-	struct wait_channel	*wc, find;
+	struct wait_channel	*wc, find = { .name = name };
+
+	if (args_has(args, 'E'))
+		return (cmd_wait_for_event(item, name, args));
 
-	find.name = name;
 	wc = RB_FIND(wait_channels, &wait_channels, &find);
-
+	if (args_has(args, 'l'))
+		return (cmd_wait_for_list(item, wc));
+	if (args_has(args, 'w'))
+		return (cmd_wait_for_wake(item, name, args, wc));
 	if (args_has(args, 'S'))
 		return (cmd_wait_for_signal(item, name, wc));
 	if (args_has(args, 'L'))
@@ -136,6 +203,179 @@ cmd_wait_for_exec(struct cmd *self, struct cmdq_item *item)
 	return (cmd_wait_for_wait(item, name, wc));
 }
 
+static void
+cmd_wait_for_event_print(struct wait_event_item *wei, struct event_payload *ep)
+{
+	struct event_payload_item	*epi;
+	const char			*key;
+	char				*value;
+
+	epi = event_payload_first(ep);
+	while (epi != NULL) {
+		key = event_payload_item_name(epi);
+		if (*key != '_') {
+			value = event_payload_item_print(epi);
+			cmdq_print(wei->item, "%s=%s", key, value);
+			free(value);
+		}
+		epi = event_payload_next(epi);
+	}
+}
+
+static void
+cmd_wait_for_event_cb(__unused const char *name, struct event_payload *ep,
+    void *item_data)
+{
+	struct wait_event_item	*wei = item_data;
+	struct format_tree	*ft;
+	char			*expanded;
+	int			 flag;
+
+	if (wei->verbose)
+		cmd_wait_for_event_print(wei, ep);
+
+	if (wei->filter != NULL) {
+		ft = format_create(cmdq_get_client(wei->item), wei->item,
+		    FORMAT_NONE, FORMAT_NOJOBS);
+		event_payload_add_formats(ep, ft, NULL);
+		expanded = format_expand(ft, wei->filter);
+		flag = format_true(expanded);
+		free(expanded);
+		format_free(ft);
+
+		if (!flag)
+			return;
+	}
+
+	TAILQ_REMOVE(&wait_event_items, wei, entry);
+	cmdq_continue(wei->item);
+	cmd_wait_for_event_free(wei);
+}
+
+static void
+cmd_wait_for_event_free(struct wait_event_item *wei)
+{
+	events_remove_sink(wei->sink);
+	free(wei->name);
+	free(wei->filter);
+	free(wei);
+}
+
+static enum cmd_retval
+cmd_wait_for_event(struct cmdq_item *item, const char *name, struct args *args)
+{
+	struct wait_event_item	*wei;
+	const char		*filter = args_get(args, 'F');
+
+	if (!hooks_valid_event_name(name)) {
+		cmdq_error(item, "invalid event: %s", name);
+		return (CMD_RETURN_ERROR);
+	}
+	if (args_has(args, 'l'))
+		return (cmd_wait_for_event_list(item, name));
+	if (args_has(args, 'w'))
+		return (cmd_wait_for_event_wake(item, name, args));
+
+	if (cmdq_get_client(item) == NULL) {
+		cmdq_error(item, "not able to wait");
+		return (CMD_RETURN_ERROR);
+	}
+
+	wei = xcalloc(1, sizeof *wei);
+	wei->item = item;
+	wei->name = xstrdup(name);
+	wei->filter = (filter != NULL ? xstrdup(filter) : NULL);
+	wei->verbose = args_has(args, 'v');
+	wei->sink = events_add_sink(name, cmd_wait_for_event_cb, wei);
+	TAILQ_INSERT_TAIL(&wait_event_items, wei, entry);
+
+	return (CMD_RETURN_WAIT);
+}
+
+static enum cmd_retval
+cmd_wait_for_event_list(struct cmdq_item *item, const char *name)
+{
+	struct wait_event_item	*wei;
+
+	TAILQ_FOREACH(wei, &wait_event_items, entry) {
+		if (strcmp(wei->name, name) == 0)
+			cmdq_print(item, "%s", cmd_wait_for_client_name(wei));
+	}
+
+	return (CMD_RETURN_NORMAL);
+}
+
+static enum cmd_retval
+cmd_wait_for_event_wake(struct cmdq_item *item, const char *name,
+    struct args *args)
+{
+	struct wait_event_item	*wei, *wei1;
+	const char		*client_name = args_get(args, 'w');
+
+	TAILQ_FOREACH_SAFE(wei, &wait_event_items, entry, wei1) {
+		if (strcmp(wei->name, name) != 0)
+			continue;
+		if (strcmp(cmd_wait_for_client_name(wei), client_name) != 0)
+			continue;
+
+		TAILQ_REMOVE(&wait_event_items, wei, entry);
+		cmdq_continue(wei->item);
+		cmd_wait_for_event_free(wei);
+		return (CMD_RETURN_NORMAL);
+	}
+
+	cmdq_error(item, "waiter %s not found", client_name);
+	return (CMD_RETURN_ERROR);
+}
+
+static enum cmd_retval
+cmd_wait_for_list(struct cmdq_item *item, struct wait_channel *wc)
+{
+	struct wait_item	*wi;
+
+	if (wc == NULL)
+		return (CMD_RETURN_NORMAL);
+
+	TAILQ_FOREACH(wi, &wc->waiters, entry)
+		cmdq_print(item, "%s", cmd_wait_for_item_client_name(wi->item));
+	TAILQ_FOREACH(wi, &wc->lockers, entry)
+		cmdq_print(item, "%s", cmd_wait_for_item_client_name(wi->item));
+
+	return (CMD_RETURN_NORMAL);
+}
+
+static enum cmd_retval
+cmd_wait_for_wake(__unused struct cmdq_item *item, const char *name,
+    struct args *args, struct wait_channel *wc)
+{
+	struct wait_item	*wi, *wi1;
+	const char		*client_name = args_get(args, 'w');
+
+	if (wc != NULL) {
+		TAILQ_FOREACH_SAFE(wi, &wc->waiters, entry, wi1) {
+			name = cmd_wait_for_item_client_name(wi->item);
+			if (strcmp(name, client_name) != 0)
+				continue;
+			cmdq_continue(wi->item);
+			TAILQ_REMOVE(&wc->waiters, wi, entry);
+			free(wi);
+			cmd_wait_for_remove_empty(wc);
+			return (CMD_RETURN_NORMAL);
+		}
+		TAILQ_FOREACH_SAFE(wi, &wc->lockers, entry, wi1) {
+			name = cmd_wait_for_item_client_name(wi->item);
+			if (strcmp(name, client_name) != 0)
+				continue;
+			cmdq_continue(wi->item);
+			TAILQ_REMOVE(&wc->lockers, wi, entry);
+			free(wi);
+			cmd_wait_for_remove_empty(wc);
+			return (CMD_RETURN_NORMAL);
+		}
+	}
+	return (CMD_RETURN_NORMAL);
+}
+
 static enum cmd_retval
 cmd_wait_for_signal(__unused struct cmdq_item *item, const char *name,
     struct wait_channel *wc)
@@ -245,6 +485,13 @@ cmd_wait_for_flush(void)
 {
 	struct wait_channel	*wc, *wc1;
 	struct wait_item	*wi, *wi1;
+	struct wait_event_item	*wei, *wei1;
+
+	TAILQ_FOREACH_SAFE(wei, &wait_event_items, entry, wei1) {
+		TAILQ_REMOVE(&wait_event_items, wei, entry);
+		cmdq_continue(wei->item);
+		cmd_wait_for_event_free(wei);
+	}
 
 	RB_FOREACH_SAFE(wc, wait_channels, &wait_channels, wc1) {
 		TAILQ_FOREACH_SAFE(wi, &wc->waiters, entry, wi1) {

cmd.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: cmd.c,v 1.185 2026/06/26 14:40:30 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

colour.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: colour.c,v 1.35 2026/07/06 14:29:10 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

control-notify.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: control-notify.c,v 1.37 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2012 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -23,33 +23,57 @@
 
 #include "tmux.h"
 
+/* Should this client be sent events? */
 #define CONTROL_SHOULD_NOTIFY_CLIENT(c) \
-	((c) != NULL && ((c)->flags & CLIENT_CONTROL) && \
+	((c) != NULL && \
+	 ((c)->flags & CLIENT_CONTROL) && \
 	 (~(c)->flags & CLIENT_EXIT) && \
 	 (c)->control_state != NULL)
 
-void
+/* Notify control clients that pane mode changed. */
-control_notify_pane_mode_changed(int pane)
+static void
+control_pane_mode_changed_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
+	struct window_pane	*wp;
 	struct client		*c;
+	char			*value;
 
+	wp = event_payload_get_pane(ep, "pane");
+	if (wp != NULL) {
 		TAILQ_FOREACH(c, &clients, entry) {
 			if (!CONTROL_SHOULD_NOTIFY_CLIENT(c))
 				continue;
-
+			control_write(c, "%%pane-mode-changed %%%u", wp->id);
-		control_write(c, "%%pane-mode-changed %%%u", pane);
 		}
+		return;
+	}
+
+	value = event_payload_print(ep, "pane");
+	if (value == NULL)
+		return;
+	TAILQ_FOREACH(c, &clients, entry) {
+		if (CONTROL_SHOULD_NOTIFY_CLIENT(c))
+			control_write(c, "%%pane-mode-changed %s", value);
+	}
+	free(value);
 }
 
-void
+/* Notify control clients that window layout changed. */
-control_notify_window_layout_changed(struct window *w)
+static void
+control_window_layout_changed_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
 	struct client		*c;
 	struct session		*s;
 	struct winlink		*wl;
+	struct window		*w = event_payload_get_window(ep, "window");
 	const char		*template;
 	char			*cp;
 
+	if (w == NULL)
+		return;
+
 	template = "%layout-change #{window_id} #{window_layout} "
 	    "#{window_visible_layout} #{window_raw_flags}";
 
@@ -73,12 +97,15 @@ control_notify_window_layout_changed(struct window *w)
 	free(cp);
 }
 
-void
+/* Notify control clients that window pane changed. */
-control_notify_window_pane_changed(struct window *w)
+static void
+control_window_pane_changed_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
 	struct client	*c;
+	struct window	*w = event_payload_get_window(ep, "window");
 
-	if (w->active == NULL)
+	if (w == NULL || w->active == NULL)
 		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c))
@@ -89,12 +116,17 @@ control_notify_window_pane_changed(struct window *w)
 	}
 }
 
-void
+/* Notify control clients that a window was unlinked. */
-control_notify_window_unlinked(__unused struct session *s, struct window *w)
+static void
+control_window_unlinked_cb(__unused const char *name, struct event_payload *ep,
+    __unused void *sink_data)
 {
 	struct client		*c;
 	struct session		*cs;
+	struct window		*w = event_payload_get_window(ep, "window");
 
+	if (w == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c) || c->session == NULL)
 			continue;
@@ -107,12 +139,17 @@ control_notify_window_unlinked(__unused struct session *s, struct window *w)
 	}
 }
 
-void
+/* Notify control clients that a window was linked. */
-control_notify_window_linked(__unused struct session *s, struct window *w)
+static void
+control_window_linked_cb(__unused const char *name, struct event_payload *ep,
+    __unused void *sink_data)
 {
 	struct client		*c;
 	struct session		*cs;
+	struct window		*w = event_payload_get_window(ep, "window");
 
+	if (w == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c) || c->session == NULL)
 			continue;
@@ -125,12 +162,17 @@ control_notify_window_linked(__unused struct session *s, struct window *w)
 	}
 }
 
-void
+/* Notify control clients that a window was renamed. */
-control_notify_window_renamed(struct window *w)
+static void
+control_window_renamed_cb(__unused const char *name, struct event_payload *ep,
+    __unused void *sink_data)
 {
 	struct client		*c;
 	struct session		*cs;
+	struct window		*w = event_payload_get_window(ep, "window");
 
+	if (w == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c) || c->session == NULL)
 			continue;
@@ -146,13 +188,16 @@ control_notify_window_renamed(struct window *w)
 	}
 }
 
-void
+/* Notify control clients that a client changed session. */
-control_notify_client_session_changed(struct client *cc)
+static void
+control_client_session_changed_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
+	struct client		*cc = event_payload_get_client(ep, "client");
 	struct client		*c;
 	struct session		*s;
 
-	if (cc->session == NULL)
+	if (cc == NULL || cc->session == NULL)
 		return;
 	s = cc->session;
 
@@ -170,22 +215,32 @@ control_notify_client_session_changed(struct client *cc)
 	}
 }
 
-void
+/* Notify control clients that a client detached. */
-control_notify_client_detached(struct client *cc)
+static void
+control_client_detached_cb(__unused const char *name, struct event_payload *ep,
+    __unused void *sink_data)
 {
+	struct client		*cc = event_payload_get_client(ep, "client");
 	struct client		*c;
 
+	if (cc == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (CONTROL_SHOULD_NOTIFY_CLIENT(c))
 			control_write(c, "%%client-detached %s", cc->name);
 	}
 }
 
-void
+/* Notify control clients that a session was renamed. */
-control_notify_session_renamed(struct session *s)
+static void
+control_session_renamed_cb(__unused const char *name, struct event_payload *ep,
+    __unused void *sink_data)
 {
+	struct session		*s = event_payload_get_session(ep, "session");
 	struct client		*c;
 
+	if (s == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c))
 			continue;
@@ -194,8 +249,10 @@ control_notify_session_renamed(struct session *s)
 	}
 }
 
-void
+/* Notify control clients that sessions changed. */
-control_notify_session_created(__unused struct session *s)
+static void
+control_session_created_cb(__unused const char *name,
+    __unused struct event_payload *ep, __unused void *sink_data)
 {
 	struct client	*c;
 
@@ -207,8 +264,10 @@ control_notify_session_created(__unused struct session *s)
 	}
 }
 
-void
+/* Notify control clients that sessions changed. */
-control_notify_session_closed(__unused struct session *s)
+static void
+control_session_closed_cb(__unused const char *name,
+    __unused struct event_payload *ep, __unused void *sink_data)
 {
 	struct client	*c;
 
@@ -220,9 +279,12 @@ control_notify_session_closed(__unused struct session *s)
 	}
 }
 
-void
+/* Notify control clients that the current window changed. */
-control_notify_session_window_changed(struct session *s)
+static void
+control_session_window_changed_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
+	struct session	*s = event_payload_get_session(ep, "session");
 	struct client	*c;
 
 	/*
@@ -230,7 +292,7 @@ control_notify_session_window_changed(struct session *s)
 	 * session has been destroyed (which sets curw to NULL) but is kept
 	 * alive by the notification's reference. Skip the notification.
 	 */
-	if (s->curw == NULL)
+	if (s == NULL || s->curw == NULL)
 		return;
 
 	TAILQ_FOREACH(c, &clients, entry) {
@@ -242,28 +304,68 @@ control_notify_session_window_changed(struct session *s)
 	}
 }
 
-void
+/* Notify control clients that a paste buffer changed. */
-control_notify_paste_buffer_changed(const char *name)
+static void
+control_paste_buffer_changed_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
+	const char	*pbname = event_payload_get_string(ep, "paste_buffer");
 	struct client	*c;
 
+	if (pbname == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c))
 			continue;
 
-		control_write(c, "%%paste-buffer-changed %s", name);
+		control_write(c, "%%paste-buffer-changed %s", pbname);
 	}
 }
 
-void
+/* Notify control clients that a paste buffer was deleted. */
-control_notify_paste_buffer_deleted(const char *name)
+static void
+control_paste_buffer_deleted_cb(__unused const char *name,
+    struct event_payload *ep, __unused void *sink_data)
 {
+	const char	*pbname = event_payload_get_string(ep, "paste_buffer");
 	struct client	*c;
 
+	if (pbname == NULL)
+		return;
 	TAILQ_FOREACH(c, &clients, entry) {
 		if (!CONTROL_SHOULD_NOTIFY_CLIENT(c))
 			continue;
 
-		control_write(c, "%%paste-buffer-deleted %s", name);
+		control_write(c, "%%paste-buffer-deleted %s", pbname);
 	}
 }
+
+/* Build control event sinks. */
+void
+control_build_events(void)
+{
+	/* Control event sink callbacks. */
+	static struct {
+		const char	*name;
+		events_cb	 cb;
+	} events[] = {
+		{ "pane-mode-changed", control_pane_mode_changed_cb },
+		{ "window-layout-changed", control_window_layout_changed_cb },
+		{ "window-pane-changed", control_window_pane_changed_cb },
+		{ "window-unlinked", control_window_unlinked_cb },
+		{ "window-linked", control_window_linked_cb },
+		{ "window-renamed", control_window_renamed_cb },
+		{ "client-session-changed", control_client_session_changed_cb },
+		{ "client-detached", control_client_detached_cb },
+		{ "session-renamed", control_session_renamed_cb },
+		{ "session-created", control_session_created_cb },
+		{ "session-closed", control_session_closed_cb },
+		{ "session-window-changed", control_session_window_changed_cb },
+		{ "paste-buffer-changed", control_paste_buffer_changed_cb },
+		{ "paste-buffer-deleted", control_paste_buffer_deleted_cb }
+	};
+	u_int	i;
+
+	for (i = 0; i < nitems(events); i++)
+		events_add_sink(events[i].name, events[i].cb, NULL);
+}

control.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: control.c,v 1.60 2026/07/10 07:25:05 nicm Exp $ */
 
 /*
  * Copyright (c) 2012 Nicholas Marriott <nicholas.marriott@gmail.com>

environ.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: environ.c,v 1.31 2026/06/13 20:07:30 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

events-payload.c

@@ -0,0 +1,672 @@
+/* $OpenBSD: events-payload.c,v 1.1 2026/07/10 13:38:45 nicm Exp $ */
+
+/*
+ * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@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 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 <event.h>
+#include <stdarg.h>
+#include <stdlib.h>
+#include <string.h>
+#include <time.h>
+
+#include "tmux.h"
+
+/* Event payload item. */
+struct event_payload_item {
+	char					*name;
+	enum event_payload_type			 type;
+
+	union {
+		char				*string;
+		time_t				 time;
+		int				 number;
+		u_int				 unsigned_number;
+		struct client			*client;
+		struct session			*session;
+		struct window			*window;
+		struct window_pane		*pane;
+		struct {
+			void			*ptr;
+			event_payload_free_cb	 free_cb;
+			event_payload_print_cb	 print_cb;
+		} pointer;
+	};
+
+	RB_ENTRY(event_payload_item)	 entry;
+};
+
+RB_HEAD(event_payload_tree, event_payload_item);
+
+struct event_payload {
+	struct event_payload_tree	 items;
+	struct cmd_find_state		 target;
+};
+
+static int
+event_payload_cmp(struct event_payload_item *epi1,
+    struct event_payload_item *epi2)
+{
+	return (strcmp(epi1->name, epi2->name));
+}
+RB_GENERATE_STATIC(event_payload_tree, event_payload_item, entry,
+    event_payload_cmp);
+
+/* Find an item. */
+static struct event_payload_item *
+event_payload_find(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	find = { .name = (char *)name };
+
+	return (RB_FIND(event_payload_tree, &ep->items, &find));
+}
+
+/* Free the target in a payload. */
+static void
+event_payload_free_target(struct event_payload *ep)
+{
+	struct cmd_find_state	*target = &ep->target;
+
+	if (target->s != NULL)
+		session_remove_ref(target->s, __func__);
+	if (target->w != NULL)
+		window_remove_ref(target->w, __func__);
+	if (target->wp != NULL)
+		window_pane_remove_ref(target->wp, __func__);
+
+	cmd_find_clear_state(target, 0);
+}
+
+/* Free the value in an item. */
+static void
+event_payload_free_value(struct event_payload_item *epi)
+{
+	switch (epi->type) {
+	case EVENT_PAYLOAD_STRING:
+		free(epi->string);
+		break;
+	case EVENT_PAYLOAD_CLIENT:
+		server_client_unref(epi->client);
+		break;
+	case EVENT_PAYLOAD_SESSION:
+		session_remove_ref(epi->session, __func__);
+		break;
+	case EVENT_PAYLOAD_WINDOW:
+		window_remove_ref(epi->window, __func__);
+		break;
+	case EVENT_PAYLOAD_PANE:
+		window_pane_remove_ref(epi->pane, __func__);
+		break;
+	case EVENT_PAYLOAD_POINTER:
+		if (epi->pointer.free_cb != NULL)
+			epi->pointer.free_cb(epi->pointer.ptr);
+		break;
+	case EVENT_PAYLOAD_INT:
+	case EVENT_PAYLOAD_UINT:
+	case EVENT_PAYLOAD_TIME:
+		break;
+	}
+}
+
+/* Set an item. */
+static void
+event_payload_set_item(struct event_payload *ep, const char *name,
+    struct event_payload_item *new)
+{
+	struct event_payload_item	*old;
+
+	new->name = xstrdup(name);
+	old = RB_INSERT(event_payload_tree, &ep->items, new);
+	if (old != NULL) {
+		RB_REMOVE(event_payload_tree, &ep->items, old);
+		event_payload_free_value(old);
+		free(old->name);
+		free(old);
+		RB_INSERT(event_payload_tree, &ep->items, new);
+	}
+}
+
+/* Create an event payload. */
+struct event_payload *
+event_payload_create(void)
+{
+	struct event_payload	*ep;
+
+	ep = xcalloc(1, sizeof *ep);
+	RB_INIT(&ep->items);
+	cmd_find_clear_state(&ep->target, 0);
+	return (ep);
+}
+
+/* Free an event payload. */
+void
+event_payload_free(struct event_payload *ep)
+{
+	struct event_payload_item	*epi, *epi1;
+
+	if (ep != NULL) {
+		RB_FOREACH_SAFE(epi, event_payload_tree, &ep->items, epi1) {
+			RB_REMOVE(event_payload_tree, &ep->items, epi);
+			event_payload_free_value(epi);
+			free(epi->name);
+			free(epi);
+		}
+		event_payload_free_target(ep);
+		free(ep);
+	}
+}
+
+/* Set the target. */
+void
+event_payload_set_target(struct event_payload *ep, struct cmd_find_state *fs)
+{
+	struct cmd_find_state	*target = &ep->target;
+
+	event_payload_free_target(ep);
+
+	if (fs->s != NULL) {
+		session_add_ref(fs->s, __func__);
+		target->s = fs->s;
+	}
+	if (fs->wl != NULL) {
+		target->idx = fs->wl->idx;
+		if (target->s == NULL) {
+			session_add_ref(fs->wl->session, __func__);
+			target->s = fs->wl->session;
+		}
+	} else
+		target->idx = -1;
+	if (fs->w != NULL) {
+		window_add_ref(fs->w, __func__);
+		target->w = fs->w;
+	} else if (fs->wl != NULL) {
+		window_add_ref(fs->wl->window, __func__);
+		target->w = fs->wl->window;
+	}
+	if (fs->wp != NULL) {
+		window_pane_add_ref(fs->wp, __func__);
+		target->wp = fs->wp;
+	}
+}
+
+/* Get the target. */
+int
+event_payload_get_target(struct event_payload *ep, struct cmd_find_state *fs)
+{
+	struct cmd_find_state	*t = &ep->target;
+	struct winlink		*wl = NULL;
+	int			 flags = fs->flags;
+
+	if (t->idx != -1 &&
+	    t->s != NULL &&
+	    t->w != NULL &&
+	    session_alive(t->s)) {
+		wl = winlink_find_by_index(&t->s->windows, t->idx);
+		if (wl != NULL && wl->window != t->w)
+			wl = NULL;
+	}
+
+	cmd_find_clear_state(fs, flags);
+	fs->s = t->s;
+	fs->w = t->w;
+	fs->wp = t->wp;
+	fs->wl = wl;
+	fs->idx = (wl != NULL ? wl->idx : -1);
+	if (cmd_find_valid_state(fs))
+		return (1);
+
+	if (wl != NULL &&
+	    t->wp != NULL &&
+	    window_has_pane(wl->window, t->wp)) {
+		cmd_find_from_winlink_pane(fs, wl, t->wp, flags);
+		if (cmd_find_valid_state(fs))
+			return (1);
+	}
+
+	if (t->wp != NULL &&
+	    cmd_find_from_pane(fs, t->wp, flags) == 0 &&
+	    cmd_find_valid_state(fs))
+		return (1);
+
+	if (wl != NULL) {
+		cmd_find_from_winlink(fs, wl, flags);
+		if (cmd_find_valid_state(fs))
+			return (1);
+	}
+
+	if (t->s != NULL &&
+	    t->w != NULL &&
+	    session_alive(t->s) &&
+	    cmd_find_from_session_window(fs, t->s, t->w, flags) == 0 &&
+	    cmd_find_valid_state(fs))
+		return (1);
+
+	if (t->s != NULL && session_alive(t->s)) {
+		cmd_find_from_session(fs, t->s, flags);
+		if (cmd_find_valid_state(fs))
+			return (1);
+	}
+
+	if (cmd_find_from_nothing(fs, flags) == 0)
+		return (1);
+
+	cmd_find_clear_state(fs, flags);
+	return (0);
+}
+
+/* Set a string item. */
+void
+event_payload_set_string(struct event_payload *ep, const char *name,
+    const char *fmt, ...)
+{
+	struct event_payload_item	*epi;
+	va_list				 ap;
+
+	va_start(ap, fmt);
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_STRING;
+	xvasprintf(&epi->string, fmt, ap);
+	event_payload_set_item(ep, name, epi);
+
+	va_end(ap);
+}
+
+/* Set a time item. */
+void
+event_payload_set_time(struct event_payload *ep, const char *name,
+    time_t value)
+{
+	struct event_payload_item	*epi;
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_TIME;
+	epi->time = value;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set a number item. */
+void
+event_payload_set_int(struct event_payload *ep, const char *name, int value)
+{
+	struct event_payload_item	*epi;
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_INT;
+	epi->number = value;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set an unsigned number item. */
+void
+event_payload_set_uint(struct event_payload *ep, const char *name, u_int value)
+{
+	struct event_payload_item	*epi;
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_UINT;
+	epi->unsigned_number = value;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set a client item. */
+void
+event_payload_set_client(struct event_payload *ep, const char *name,
+    struct client *c)
+{
+	struct event_payload_item	*epi;
+
+	c->references++;
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_CLIENT;
+	epi->client = c;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set a session item. */
+void
+event_payload_set_session(struct event_payload *ep, const char *name,
+    struct session *s)
+{
+	struct event_payload_item	*epi;
+
+	session_add_ref(s, __func__);
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_SESSION;
+	epi->session = s;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set a window item. */
+void
+event_payload_set_window(struct event_payload *ep, const char *name,
+    struct window *w)
+{
+	struct event_payload_item	*epi;
+
+	window_add_ref(w, __func__);
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_WINDOW;
+	epi->window = w;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set a pane item. */
+void
+event_payload_set_pane(struct event_payload *ep, const char *name,
+    struct window_pane *wp)
+{
+	struct event_payload_item	*epi;
+
+	window_pane_add_ref(wp, __func__);
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_PANE;
+	epi->pane = wp;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Set a pointer item. */
+void
+event_payload_set_pointer(struct event_payload *ep, const char *name,
+    void *ptr, event_payload_free_cb free_cb, event_payload_print_cb print_cb)
+{
+	struct event_payload_item	*epi;
+
+	epi = xcalloc(1, sizeof *epi);
+	epi->type = EVENT_PAYLOAD_POINTER;
+	epi->pointer.ptr = ptr;
+	epi->pointer.free_cb = free_cb;
+	epi->pointer.print_cb = print_cb;
+	event_payload_set_item(ep, name, epi);
+}
+
+/* Get a string item. */
+const char *
+event_payload_get_string(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_STRING)
+		return (NULL);
+	return (epi->string);
+}
+
+/* Print a payload item. */
+static void
+event_payload_add_item(struct event_payload_item *epi, struct evbuffer *evb)
+{
+	switch (epi->type) {
+	case EVENT_PAYLOAD_STRING:
+		evbuffer_add_printf(evb, "%s", epi->string);
+		break;
+	case EVENT_PAYLOAD_TIME:
+		evbuffer_add_printf(evb, "%lld", (long long)epi->time);
+		break;
+	case EVENT_PAYLOAD_INT:
+		evbuffer_add_printf(evb, "%d", epi->number);
+		break;
+	case EVENT_PAYLOAD_UINT:
+		evbuffer_add_printf(evb, "%u", epi->unsigned_number);
+		break;
+	case EVENT_PAYLOAD_CLIENT:
+		evbuffer_add_printf(evb, "%s", epi->client->name);
+		break;
+	case EVENT_PAYLOAD_SESSION:
+		evbuffer_add_printf(evb, "$%u", epi->session->id);
+		break;
+	case EVENT_PAYLOAD_WINDOW:
+		evbuffer_add_printf(evb, "@%u", epi->window->id);
+		break;
+	case EVENT_PAYLOAD_PANE:
+		evbuffer_add_printf(evb, "%%%u", epi->pane->id);
+		break;
+	case EVENT_PAYLOAD_POINTER:
+		if (epi->pointer.print_cb != NULL)
+			epi->pointer.print_cb(epi->pointer.ptr, evb);
+		else
+			evbuffer_add_printf(evb, "%p", epi->pointer.ptr);
+		break;
+	}
+}
+
+/* Print a payload item. */
+char *
+event_payload_item_print(struct event_payload_item *epi)
+{
+	struct evbuffer			*evb;
+	char				*value = NULL;
+	size_t				 size;
+
+	evb = evbuffer_new();
+	if (evb == NULL)
+		fatalx("out of memory");
+	event_payload_add_item(epi, evb);
+	if ((size = EVBUFFER_LENGTH(evb)) != 0)
+		value = xmemdup(EVBUFFER_DATA(evb), size);
+	else
+		value = xstrdup("");
+	evbuffer_free(evb);
+	return (value);
+}
+
+/* Print an item value. */
+char *
+event_payload_print(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL)
+		return (NULL);
+	return (event_payload_item_print(epi));
+}
+
+/* Add payload items as formats. */
+void
+event_payload_add_formats(struct event_payload *ep, struct format_tree *ft,
+    const char *prefix)
+{
+	struct event_payload_item	*epi;
+	char				*name, *value;
+	const char			*key;
+
+	if (prefix == NULL)
+		prefix = "";
+
+	RB_FOREACH(epi, event_payload_tree, &ep->items) {
+		key = epi->name;
+		if (*key == '_')
+			continue;
+
+		value = event_payload_item_print(epi);
+		xasprintf(&name, "%s%s", prefix, key);
+		format_add(ft, name, "%s", value);
+		free(name);
+		free(value);
+
+		if (epi->type == EVENT_PAYLOAD_SESSION) {
+			xasprintf(&name, "%s%s_name", prefix, key);
+			format_add(ft, name, "%s", epi->session->name);
+			free(name);
+		} else if (epi->type == EVENT_PAYLOAD_WINDOW) {
+			xasprintf(&name, "%s%s_name", prefix, key);
+			format_add(ft, name, "%s", epi->window->name);
+			free(name);
+		}
+	}
+}
+
+/* Get the first payload item. */
+struct event_payload_item *
+event_payload_first(struct event_payload *ep)
+{
+	return (RB_MIN(event_payload_tree, &ep->items));
+}
+
+/* Get the next payload item. */
+struct event_payload_item *
+event_payload_next(struct event_payload_item *epi)
+{
+	return (RB_NEXT(event_payload_tree, , epi));
+}
+
+/* Get a payload item name. */
+const char *
+event_payload_item_name(struct event_payload_item *epi)
+{
+	return (epi->name);
+}
+
+/* Get a payload item type. */
+enum event_payload_type
+event_payload_item_type(struct event_payload_item *epi)
+{
+	return (epi->type);
+}
+
+/* Log a payload. */
+void
+event_payload_log(struct event_payload *ep, const char *fmt, ...)
+{
+	struct event_payload_item	*epi;
+	struct evbuffer			*evb;
+	va_list				 ap;
+	char				*prefix;
+
+	va_start(ap, fmt);
+	xvasprintf(&prefix, fmt, ap);
+	va_end(ap);
+
+	evb = evbuffer_new();
+	if (evb == NULL)
+		fatalx("out of memory");
+	if (ep != NULL) {
+		RB_FOREACH(epi, event_payload_tree, &ep->items) {
+			if (EVBUFFER_LENGTH(evb) != 0)
+				evbuffer_add_printf(evb, ", ");
+			evbuffer_add_printf(evb, "%s=", epi->name);
+			event_payload_add_item(epi, evb);
+		}
+	}
+	log_debug("%s%.*s", prefix, (int)EVBUFFER_LENGTH(evb),
+	    (char *)EVBUFFER_DATA(evb));
+	evbuffer_free(evb);
+	free(prefix);
+}
+
+/* Get a time item. */
+time_t
+event_payload_get_time(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_TIME)
+		return (0);
+	return (epi->time);
+}
+
+/* Get a number item. */
+int
+event_payload_get_int(struct event_payload *ep, const char *name, int *value)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_INT)
+		return (-1);
+	*value = epi->number;
+	return (0);
+}
+
+/* Get an unsigned number item. */
+int
+event_payload_get_uint(struct event_payload *ep, const char *name, u_int *value)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_UINT)
+		return (-1);
+	*value = epi->unsigned_number;
+	return (0);
+}
+
+/* Get a client item. */
+struct client *
+event_payload_get_client(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_CLIENT)
+		return (NULL);
+	return (epi->client);
+}
+
+/* Get a session item. */
+struct session *
+event_payload_get_session(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_SESSION)
+		return (NULL);
+	return (epi->session);
+}
+
+/* Get a window item. */
+struct window *
+event_payload_get_window(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_WINDOW)
+		return (NULL);
+	return (epi->window);
+}
+
+/* Get a pane item. */
+struct window_pane *
+event_payload_get_pane(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_PANE)
+		return (NULL);
+	return (epi->pane);
+}
+
+/* Get a pointer item. */
+void *
+event_payload_get_pointer(struct event_payload *ep, const char *name)
+{
+	struct event_payload_item	*epi;
+
+	epi = event_payload_find(ep, name);
+	if (epi == NULL || epi->type != EVENT_PAYLOAD_POINTER)
+		return (NULL);
+	return (epi->pointer.ptr);
+}

events.c

@@ -0,0 +1,199 @@
+/* $OpenBSD: events.c,v 1.1 2026/07/10 13:38:45 nicm Exp $ */
+
+/*
+ * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@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 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"
+
+/* Event sink. */
+struct events_sink {
+	char				*name;
+	events_cb			 cb;
+	void				*data;
+	int				 dead;
+	u_int				 generation;
+
+	TAILQ_ENTRY(events_sink)	 entry;
+};
+
+TAILQ_HEAD(events_sinks, events_sink);
+static struct events_sinks events_sinks = TAILQ_HEAD_INITIALIZER(events_sinks);
+
+static u_int events_dispatching;
+static u_int events_generation;
+
+/* Free an event sink. */
+static void
+events_free_sink(struct events_sink *es)
+{
+	TAILQ_REMOVE(&events_sinks, es, entry);
+	free(es->name);
+	free(es);
+}
+
+/* Free dead event sinks. */
+static void
+events_free_dead(void)
+{
+	struct events_sink	*es, *es1;
+
+	TAILQ_FOREACH_SAFE(es, &events_sinks, entry, es1) {
+		if (es->dead)
+			events_free_sink(es);
+	}
+}
+
+/* Add an event sink. */
+struct events_sink *
+events_add_sink(const char *name, events_cb cb, void *data)
+{
+	struct events_sink	*es;
+
+	es = xcalloc(1, sizeof *es);
+	es->name = xstrdup(name);
+	es->cb = cb;
+	es->data = data;
+	es->generation = ++events_generation;
+
+	TAILQ_INSERT_TAIL(&events_sinks, es, entry);
+	return (es);
+}
+
+/* Remove an event sink. */
+void
+events_remove_sink(struct events_sink *es)
+{
+	if (es != NULL && !es->dead) {
+		if (events_dispatching != 0)
+			es->dead = 1;
+		else
+			events_free_sink(es);
+	}
+}
+
+/* Fire an event. */
+void
+events_fire(const char *name, struct event_payload *ep)
+{
+	struct events_sink	*es;
+	u_int			 generation = events_generation;
+
+	event_payload_set_string(ep, "event", "%s", name);
+
+	if (log_get_level() != 0)
+		event_payload_log(ep, "%s: %s: ", __func__, name);
+
+	events_dispatching++;
+	TAILQ_FOREACH(es, &events_sinks, entry) {
+		if (es->dead || es->generation > generation)
+			continue;
+		if (strcmp(es->name, name) == 0)
+			es->cb(name, ep, es->data);
+	}
+	if (--events_dispatching == 0)
+		events_free_dead();
+	event_payload_free(ep);
+}
+
+/* Fire a client event. */
+void
+events_fire_client(const char *name, struct client *c)
+{
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	cmd_find_from_client(&fs, c, 0);
+	event_payload_set_target(ep, &fs);
+	event_payload_set_client(ep, "client", c);
+	if (fs.s != NULL)
+		event_payload_set_session(ep, "session", fs.s);
+	if (fs.w != NULL)
+		event_payload_set_window(ep, "window", fs.w);
+	if (fs.wl != NULL)
+		event_payload_set_int(ep, "window_index", fs.wl->idx);
+	else if (fs.idx != -1)
+		event_payload_set_int(ep, "window_index", fs.idx);
+	if (fs.wp != NULL)
+		event_payload_set_pane(ep, "pane", fs.wp);
+	events_fire(name, ep);
+}
+
+/* Fire a session event. */
+void
+events_fire_session(const char *name, struct session *s)
+{
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	if (session_alive(s)) {
+		cmd_find_from_session(&fs, s, 0);
+		event_payload_set_target(ep, &fs);
+	}
+	event_payload_set_session(ep, "session", s);
+	events_fire(name, ep);
+}
+
+/* Fire a window event. */
+void
+events_fire_window(const char *name, struct window *w)
+{
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	cmd_find_from_window(&fs, w, 0);
+	event_payload_set_target(ep, &fs);
+	event_payload_set_window(ep, "window", w);
+	events_fire(name, ep);
+}
+
+/* Fire a pane event. */
+void
+events_fire_pane(const char *name, struct window_pane *wp)
+{
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	cmd_find_from_pane(&fs, wp, 0);
+	event_payload_set_target(ep, &fs);
+	event_payload_set_pane(ep, "pane", wp);
+	event_payload_set_window(ep, "window", wp->window);
+	events_fire(name, ep);
+}
+
+/* Fire a winlink event. */
+void
+events_fire_winlink(const char *name, struct winlink *wl)
+{
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	cmd_find_from_winlink(&fs, wl, 0);
+	event_payload_set_target(ep, &fs);
+	event_payload_set_session(ep, "session", wl->session);
+	event_payload_set_window(ep, "window", wl->window);
+	event_payload_set_int(ep, "window_index", wl->idx);
+	events_fire(name, ep);
+}

file.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: file.c,v 1.20 2026/05/17 10:54:01 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>

format-draw.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: format-draw.c,v 1.33 2026/06/29 17:08:52 nicm Exp $ */
 
 /*
  * Copyright (c) 2019 Nicholas Marriott <nicholas.marriott@gmail.com>

format.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: format.c,v 1.402 2026/07/09 06:33:19 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 Nicholas Marriott <nicholas.marriott@gmail.com>

fuzzy.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: fuzzy.c,v 1.1 2026/06/26 14:40:30 nicm Exp $ */
 
 /*
  * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@gmail.com>

grid-reader.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: grid-reader.c,v 1.10 2026/05/17 13:12:21 nicm Exp $ */
 
 /*
  * Copyright (c) 2020 Anindya Mukherjee <anindya49@hotmail.com>

grid-view.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: grid-view.c,v 1.38 2026/01/22 08:55:01 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

grid.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: grid.c,v 1.153 2026/07/02 08:51:05 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>

hooks.c

@@ -0,0 +1,461 @@
+/* $OpenBSD: hooks.c,v 1.12 2026/07/10 13:38:45 nicm Exp $ */
+
+/*
+ * Copyright (c) 2026 Nicholas Marriott <nicholas.marriott@gmail.com>
+ * Copyright (c) 2012 George Nachman <tmux@georgester.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"
+
+/* Hook monitor state owned by an option entry. */
+struct hook_monitor {
+	struct options		*oo;
+
+	struct monitor_set	*set;
+	struct events_sink	*sink;
+	struct cmd_find_state	 fs;
+
+	enum monitor_type	 type;
+	int			 id;
+	char			*format;
+};
+
+/* Hook command data built from an event payload. */
+struct hooks_data {
+	const char		*name;
+	struct cmd_find_state	 fs;
+	struct format_tree	*formats;
+	struct options		*oo;
+	struct client		*client;
+	int			 expand;
+};
+
+/* Hook event sink registered for a notify event name. */
+struct hooks_event {
+	char			*name;
+	struct events_sink	*sink;
+	TAILQ_ENTRY(hooks_event) entry;
+};
+TAILQ_HEAD(hooks_events, hooks_event);
+static struct hooks_events hooks_events = TAILQ_HEAD_INITIALIZER(hooks_events);
+
+/* Insert one hook command list. */
+static struct cmdq_item *
+hooks_insert_one(struct cmdq_item *item, struct hooks_data *hd,
+    struct cmd_list *cmdlist, struct cmdq_state *state)
+{
+	struct cmdq_item	*new_item;
+	char			*s;
+
+	if (cmdlist == NULL)
+		return (item);
+	if (log_get_level() != 0) {
+		s = cmd_list_print(cmdlist, 0);
+		log_debug("%s: hook %s is: %s", __func__, hd->name, s);
+		free(s);
+	}
+	new_item = cmdq_get_command(cmdlist, state);
+	if (item != NULL)
+		return (cmdq_insert_after(item, new_item));
+	return (cmdq_append(NULL, new_item));
+}
+
+/* Parse a hook command. */
+static struct cmd_parse_result *
+hooks_parse(struct hooks_data *hd, struct cmd_find_state *fs,
+    const char *value)
+{
+	struct cmd_parse_result	*pr;
+	struct format_tree	*ft;
+	char			*expanded;
+
+	if (!hd->expand)
+		return (cmd_parse_from_string(value, NULL));
+
+	ft = format_create_defaults(NULL, hd->client, fs->s, fs->wl, fs->wp);
+	if (hd->formats != NULL)
+		format_merge(ft, hd->formats);
+	expanded = format_expand(ft, value);
+	format_free(ft);
+
+	pr = cmd_parse_from_string(expanded, NULL);
+	free(expanded);
+	return (pr);
+}
+
+/* Insert commands for a hook. */
+static void
+hooks_insert(struct cmdq_item *item, struct hooks_data *hd)
+{
+	struct cmd_find_state		 fs;
+	struct options			*oo;
+	struct cmdq_state		*state;
+	struct options_entry		*o;
+	struct options_array_item	*a;
+	struct cmd_list			*cmdlist;
+	const char			*value;
+	struct cmd_parse_result		*pr;
+
+	log_debug("%s: inserting hook %s", __func__, hd->name);
+
+	cmd_find_clear_state(&fs, 0);
+	if (cmd_find_empty_state(&hd->fs) || !cmd_find_valid_state(&hd->fs))
+		cmd_find_from_nothing(&fs, 0);
+	else
+		cmd_find_copy_state(&fs, &hd->fs);
+
+	if (hd->oo != NULL) {
+		oo = hd->oo;
+		o = options_get_only(oo, hd->name);
+	} else {
+		if (fs.s == NULL)
+			oo = global_s_options;
+		else
+			oo = fs.s->options;
+		o = options_get(oo, hd->name);
+		if (o == NULL && fs.wp != NULL) {
+			oo = fs.wp->options;
+			o = options_get(oo, hd->name);
+		}
+		if (o == NULL && fs.wl != NULL) {
+			oo = fs.wl->window->options;
+			o = options_get(oo, hd->name);
+		}
+	}
+	if (o == NULL) {
+		log_debug("%s: hook %s not found", __func__, hd->name);
+		return;
+	}
+
+	if (item == NULL)
+		state = cmdq_new_state(&fs, NULL, CMDQ_STATE_NOHOOKS);
+	else {
+		state = cmdq_new_state(&fs, cmdq_get_event(item),
+		    CMDQ_STATE_NOHOOKS);
+	}
+	cmdq_add_formats(state, hd->formats);
+
+	if (*hd->name == '@') {
+		value = options_get_string(oo, hd->name);
+		pr = hooks_parse(hd, &fs, value);
+		switch (pr->status) {
+		case CMD_PARSE_ERROR:
+			log_debug("%s: can't parse hook %s: %s", __func__,
+			    hd->name, pr->error);
+			free(pr->error);
+			break;
+		case CMD_PARSE_SUCCESS:
+			hooks_insert_one(item, hd, pr->cmdlist, state);
+			break;
+		}
+	} else {
+		a = options_array_first(o);
+		while (a != NULL) {
+			if (hd->expand) {
+				value = options_array_item_value(a)->string;
+				pr = hooks_parse(hd, &fs, value);
+				switch (pr->status) {
+				case CMD_PARSE_ERROR:
+					if (pr->error != NULL) {
+						cmdq_error(item, "%s",
+						    pr->error);
+					}
+					break;
+				case CMD_PARSE_SUCCESS:
+					item = hooks_insert_one(item, hd,
+					    pr->cmdlist, state);
+					break;
+				}
+			} else {
+				cmdlist = options_array_item_value(a)->cmdlist;
+				item = hooks_insert_one(item, hd, cmdlist,
+				    state);
+			}
+			a = options_array_next(a);
+		}
+	}
+
+	cmdq_free_state(state);
+}
+
+/* Insert commands for a hook event. */
+static void
+hooks_insert_event(struct cmdq_item *item, const char *name,
+    struct event_payload *ep, struct options *oo, int expand)
+{
+	struct hooks_data	 hd;
+	struct format_tree	*ft;
+	struct client		*c;
+
+	if (item != NULL && (cmdq_get_flags(item) & CMDQ_STATE_NOHOOKS))
+		return;
+
+	c = event_payload_get_client(ep, "client");
+	ft = format_create(c, item, FORMAT_NONE, FORMAT_NOJOBS);
+	event_payload_add_formats(ep, ft, "hook_");
+	format_add(ft, "hook", "%s", name);
+	format_log_debug(ft, __func__);
+
+	memset(&hd, 0, sizeof hd);
+	hd.name = name;
+	cmd_find_clear_state(&hd.fs, 0);
+	event_payload_get_target(ep, &hd.fs);
+	hd.formats = ft;
+	hd.oo = oo;
+	hd.client = c;
+	hd.expand = expand;
+
+	hooks_insert(item, &hd);
+	format_free(ft);
+}
+
+/* Handle an event for hooks. */
+static void
+hooks_event_cb(const char *name, struct event_payload *ep,
+    __unused void *sink_data)
+{
+	struct cmdq_item	*item;
+
+	if (event_payload_get_pointer(ep, "_hook_monitor") != NULL)
+		return;
+
+	item = event_payload_get_pointer(ep, "_cmdq_item");
+	if (item != NULL) {
+		hooks_insert_event(item, name, ep, NULL, 0);
+		return;
+	}
+
+	item = cmdq_running(NULL);
+	if (item == NULL || (~cmdq_get_flags(item) & CMDQ_STATE_NOHOOKS))
+		hooks_insert_event(NULL, name, ep, NULL, 0);
+}
+
+/* Add a hook event sink. */
+void
+hooks_add_event(const char *name)
+{
+	struct hooks_event	*he;
+
+	TAILQ_FOREACH(he, &hooks_events, entry) {
+		if (strcmp(he->name, name) == 0)
+			return;
+	}
+
+	he = xcalloc(1, sizeof *he);
+	he->name = xstrdup(name);
+	he->sink = events_add_sink(name, hooks_event_cb, NULL);
+	TAILQ_INSERT_TAIL(&hooks_events, he, entry);
+}
+
+/* Return if an event name can be fired through the hooks path. */
+int
+hooks_valid_event_name(const char *name)
+{
+	const struct options_table_entry	*oe;
+
+	if (*name == '@')
+		return (1);
+	oe = options_search(name);
+	return (oe != NULL && (oe->flags & OPTIONS_TABLE_IS_HOOK));
+}
+
+/* Add hook event sinks for all built-in hooks. */
+void
+hooks_build_events(void)
+{
+	const struct options_table_entry	*oe;
+
+	for (oe = options_table; oe->name != NULL; oe++) {
+		if (oe->flags & OPTIONS_TABLE_IS_HOOK)
+			hooks_add_event(oe->name);
+	}
+}
+
+/* Run a hook immediately. */
+void
+hooks_run(struct cmdq_item *item, const char *name)
+{
+	struct cmd_find_state	*target = cmdq_get_target(item);
+	struct hooks_data	 hd = { 0 };
+
+	hd.name = name;
+	cmd_find_copy_state(&hd.fs, target);
+	hd.client = cmdq_get_client(item);
+
+	hd.formats = format_create(NULL, NULL, 0, FORMAT_NOJOBS);
+	format_add(hd.formats, "hook", "%s", name);
+	format_log_debug(hd.formats, __func__);
+
+	hooks_insert(item, &hd);
+	format_free(hd.formats);
+}
+
+/* Free a hook monitor. */
+void
+hooks_monitor_free(void *data)
+{
+	struct hook_monitor	*hm = data;
+
+	events_remove_sink(hm->sink);
+	monitor_destroy(hm->set);
+	free(hm->format);
+	free(hm);
+}
+
+/* Remove a hook monitor. */
+void
+hooks_monitor_remove(struct options *oo, const char *name)
+{
+	struct options_entry	*o;
+	struct hook_monitor	*hm;
+
+	o = options_get_only(oo, name);
+	if (o == NULL)
+		return;
+
+	hm = options_get_monitor_data(o);
+	if (hm != NULL) {
+		options_set_monitor_data(o, NULL);
+		hooks_monitor_free(hm);
+	}
+}
+
+/* Handle a hook monitor event. */
+static void
+hooks_monitor_hook_cb(const char *name, struct event_payload *ep,
+    void *sink_data)
+{
+	struct hook_monitor	*hm = sink_data;
+
+	if (event_payload_get_pointer(ep, "_hook_monitor") == hm)
+		hooks_insert_event(cmdq_running(NULL), name, ep, hm->oo, 1);
+}
+
+/* Fire a hook monitor event. */
+static void
+hooks_monitor_cb(struct monitor_change *change, void *data)
+{
+	struct hook_monitor	*hm = data;
+	struct event_payload	*ep;
+	struct winlink		*wl = change->wl;
+	struct window_pane	*wp = change->wp;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	event_payload_set_pointer(ep, "_hook_monitor", data, NULL, NULL);
+
+	cmd_find_clear_state(&fs, 0);
+	if (wl != NULL && wp != NULL && wp->window == wl->window)
+		cmd_find_from_winlink_pane(&fs, wl, wp, 0);
+	else if (wl != NULL)
+		cmd_find_from_winlink(&fs, wl, 0);
+	else if (wp != NULL)
+		cmd_find_from_pane(&fs, wp, 0);
+	else if (change->s != NULL)
+		cmd_find_from_session(&fs, change->s, 0);
+	else
+		cmd_find_copy_state(&fs, &hm->fs);
+	event_payload_set_target(ep, &fs);
+
+	if (change->value != NULL)
+		event_payload_set_string(ep, "value", "%s", change->value);
+	else
+		event_payload_set_string(ep, "value", "%s", "");
+	if (change->last != NULL)
+		event_payload_set_string(ep, "last", "%s", change->last);
+	else
+		event_payload_set_string(ep, "last", "%s", "");
+
+	if (change->c != NULL)
+		event_payload_set_client(ep, "client", change->c);
+	if (change->s != NULL)
+		event_payload_set_session(ep, "session", change->s);
+	if (wl != NULL) {
+		if (change->s == NULL)
+			event_payload_set_session(ep, "session",
+			    wl->session);
+		event_payload_set_window(ep, "window", wl->window);
+		event_payload_set_int(ep, "window_index", wl->idx);
+	}
+	if (wp != NULL) {
+		event_payload_set_pane(ep, "pane", wp);
+		if (wl == NULL)
+			event_payload_set_window(ep, "window", wp->window);
+	}
+
+	events_fire(change->name, ep);
+}
+
+/* Add a hook monitor. */
+void
+hooks_monitor_add(__unused struct cmdq_item *item, struct options *oo,
+    const char *name, enum monitor_type type, int id, const char *format,
+    struct cmd_find_state *fs, struct session *s)
+{
+	struct options_entry	*o;
+	struct hook_monitor	*hm;
+
+	hooks_monitor_remove(oo, name);
+	o = options_get_only(oo, name);
+	if (o == NULL)
+		o = options_set_string(oo, name, 0, "%s", "");
+
+	hm = xcalloc(1, sizeof *hm);
+	hm->oo = oo;
+	cmd_find_copy_state(&hm->fs, fs);
+	hm->type = type;
+	hm->id = id;
+	hm->format = xstrdup(format);
+	hm->set = monitor_create_session(s, hooks_monitor_cb, hm);
+	hm->sink = events_add_sink(name, hooks_monitor_hook_cb, hm);
+	options_set_monitor_data(o, hm);
+	monitor_add(hm->set, name, type, id, format, 0);
+}
+
+/* Convert a hook monitor to its value. */
+char *
+hooks_monitor_to_string(struct options_entry *o)
+{
+	struct hook_monitor	*hm = options_get_monitor_data(o);
+	const char		*name = options_name(o);
+	char			*s;
+
+	if (hm == NULL)
+		return (NULL);
+
+	switch (hm->type) {
+	case MONITOR_SESSION:
+		xasprintf(&s, "%s::%s", name, hm->format);
+		break;
+	case MONITOR_PANE:
+		xasprintf(&s, "%s:%%%d:%s", name, hm->id, hm->format);
+		break;
+	case MONITOR_ALL_PANES:
+		xasprintf(&s, "%s:%%*:%s", name, hm->format);
+		break;
+	case MONITOR_WINDOW:
+		xasprintf(&s, "%s:@%d:%s", name, hm->id, hm->format);
+		break;
+	case MONITOR_ALL_WINDOWS:
+		xasprintf(&s, "%s:@*:%s", name, hm->format);
+		break;
+	}
+	return (s);
+}

hyperlinks.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: hyperlinks.c,v 1.5 2026/06/29 16:44:06 nicm Exp $ */
 
 /*
  * Copyright (c) 2021 Will <author@will.party>

input-keys.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: input-keys.c,v 1.114 2026/06/15 21:47:01 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

input.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: input.c,v 1.265 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -174,6 +174,8 @@ static void	input_osc_110(struct input_ctx *, const char *);
 static void	input_osc_111(struct input_ctx *, const char *);
 static void	input_osc_112(struct input_ctx *, const char *);
 static void	input_osc_133(struct input_ctx *, const char *);
+static void	input_fire_pane_title_changed(struct window_pane *,
+		    const char *);
 
 /* Transition entry/exit handlers. */
 static void	input_clear(struct input_ctx *);
@@ -210,6 +212,21 @@ static int	input_end_bel(struct input_ctx *);
 /* Command table comparison function. */
 static int	input_table_compare(const void *, const void *);
 
+static void
+input_fire_pane_title_changed(struct window_pane *wp, const char *title)
+{
+	struct event_payload	*ep;
+	struct cmd_find_state	 fs;
+
+	ep = event_payload_create();
+	cmd_find_from_pane(&fs, wp, 0);
+	event_payload_set_target(ep, &fs);
+	event_payload_set_pane(ep, "pane", wp);
+	event_payload_set_window(ep, "window", wp->window);
+	event_payload_set_string(ep, "new_title", "%s", title);
+	events_fire("pane-title-changed", ep);
+}
+
 /* Command table entry. */
 struct input_table_entry {
 	int		ch;
@@ -2161,7 +2178,7 @@ input_csi_dispatch_winops(struct input_ctx *ictx)
 				screen_pop_title(sctx->s);
 				if (wp == NULL)
 					break;
-				notify_pane("pane-title-changed", wp);
+				events_fire_pane("pane-title-changed", wp);
 				server_redraw_window_borders(w);
 				server_status_window(w);
 				break;
@@ -2663,7 +2680,7 @@ input_exit_osc(struct input_ctx *ictx)
 		if (wp != NULL &&
 		    options_get_number(wp->options, "allow-set-title") &&
 		    screen_set_title(sctx->s, p, 1)) {
-			notify_pane("pane-title-changed", wp);
+			input_fire_pane_title_changed(wp, p);
 			server_redraw_window_borders(wp->window);
 			server_status_window(wp->window);
 		}
@@ -2741,7 +2758,7 @@ input_exit_apc(struct input_ctx *ictx)
 	if (wp != NULL &&
 	    options_get_number(wp->options, "allow-set-title") &&
 	    screen_set_title(sctx->s, ictx->input_buf, 1)) {
-		notify_pane("pane-title-changed", wp);
+		input_fire_pane_title_changed(wp, ictx->input_buf);
 		server_redraw_window_borders(wp->window);
 		server_status_window(wp->window);
 	}
@@ -3252,7 +3269,7 @@ input_osc_52(struct input_ctx *ictx, const char *p)
 		screen_write_start_pane(&ctx, wp, NULL);
 		screen_write_setselection(&ctx, clip, out, outlen);
 		screen_write_stop(&ctx);
-		notify_pane("pane-set-clipboard", wp);
+		events_fire_pane("pane-set-clipboard", wp);
 		paste_add(NULL, out, outlen);
 	}
 }

job.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: job.c,v 1.74 2025/09/08 11:21:56 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>

key-bindings.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: key-bindings.c,v 1.186 2026/07/07 12:30:36 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

key-string.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: key-string.c,v 1.77 2026/03/31 11:46:43 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>

layout-custom.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: layout-custom.c,v 1.37 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2010 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -286,7 +286,7 @@ layout_parse(struct window *w, const char *layout, char **cause)
 	recalculate_sizes();
 	layout_print_cell(tiled_lc, __func__, 0);
 
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 
 	return (0);
 

layout-set.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: layout-set.c,v 1.39 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -183,7 +183,7 @@ layout_set_even(struct window *w, enum layout_type type)
 	layout_print_cell(w->layout_root, __func__, 1);
 
 	window_resize(w, lcroot->g.sx, lcroot->g.sy, -1, -1);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 }
 
@@ -292,7 +292,7 @@ layout_set_main_h(struct window *w)
 	layout_print_cell(w->layout_root, __func__, 1);
 
 	window_resize(w, lcroot->g.sx, lcroot->g.sy, -1, -1);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 }
 
@@ -389,7 +389,7 @@ layout_set_main_h_mirrored(struct window *w)
 	layout_print_cell(w->layout_root, __func__, 1);
 
 	window_resize(w, lcroot->g.sx, lcroot->g.sy, -1, -1);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 }
 
@@ -486,7 +486,7 @@ layout_set_main_v(struct window *w)
 	layout_print_cell(w->layout_root, __func__, 1);
 
 	window_resize(w, lcroot->g.sx, lcroot->g.sy, -1, -1);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 }
 
@@ -584,7 +584,7 @@ layout_set_main_v_mirrored(struct window *w)
 	layout_print_cell(w->layout_root, __func__, 1);
 
 	window_resize(w, lcroot->g.sx, lcroot->g.sy, -1, -1);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 }
 
@@ -706,6 +706,6 @@ layout_set_tiled(struct window *w)
 	layout_print_cell(w->layout_root, __func__, 1);
 
 	window_resize(w, lcroot->g.sx, lcroot->g.sy, -1, -1);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 	server_redraw_window(w);
 }

layout.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: layout.c,v 1.93 2026/07/10 13:38:45 nicm Exp $ */
 
 /*
  * Copyright (c) 2009 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -957,7 +957,7 @@ layout_resize_layout(struct window *w, struct layout_cell *lc,
 	/* Fix cell offsets. */
 	layout_fix_offsets(w);
 	layout_fix_panes(w, NULL);
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 }
 
 /* Resize a single pane within the layout. */
@@ -1502,7 +1502,7 @@ layout_close_pane(struct window_pane *wp)
 		layout_fix_offsets(w);
 		layout_fix_panes(w, NULL);
 	}
-	notify_window("window-layout-changed", w);
+	events_fire_window("window-layout-changed", w);
 }
 
 /* Spread out cells inside a parent cell. */

log.c

@@ -1,4 +1,4 @@
-/* $OpenBSD$ */
+/* $OpenBSD: log.c,v 1.33 2026/05/17 16:02:33 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>