Add format variables for the cmdline property to OSC 133, GitHub issue 5711.

format.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: format.c,v 1.427 2026/10/12 12:22:42 nicm Exp $ */
+/* $OpenBSD: format.c,v 1.428 2026/10/13 10:21:58 nicm Exp $ */
 
 /*
  * Copyright (c) 2011 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -2340,6 +2340,17 @@ format_cb_pane_last_prompt_time(struct format_tree *ft)
 	return (NULL);
 }
 
+/* Callback for pane_command_line. */
+static void *
+format_cb_pane_command_line(struct format_tree *ft)
+{
+	struct window_pane	*wp = ft->wp;
+
+	if (wp != NULL && wp->cmd_line != NULL)
+		return (xstrdup(wp->cmd_line));
+	return (NULL);
+}
+
 /* Callback for pane_command_start_time. */
 static void *
 format_cb_pane_command_start_time(struct format_tree *ft)
@@ -3825,6 +3836,9 @@ static const struct format_table_entry format_table[] = {
 	{ "pane_command_end_time", FORMAT_TABLE_TIME,
 	  format_cb_pane_command_end_time
 	},
+	{ "pane_command_line", FORMAT_TABLE_STRING,
+	  format_cb_pane_command_line
+	},
 	{ "pane_command_running", FORMAT_TABLE_STRING,
 	  format_cb_pane_command_running
 	},

input.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: input.c,v 1.275 2026/10/12 18:47:52 nicm Exp $ */
+/* $OpenBSD: input.c,v 1.276 2026/10/13 10:21:58 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -3186,6 +3186,52 @@ input_osc_133_exit_status(const char *p)
 	return (status);
 }
 
+/* Parse and clean the URL-encoded command line from OSC 133 C. */
+static char *
+input_osc_133_command_line(const char *p)
+{
+	const char	*end;
+	char		 line[16385], h[3] = { 0 };
+	size_t		 size = 0;
+	u_char		 ch;
+
+	if (p[1] != ';')
+		return (NULL);
+	p += 2;
+	for (;;) {
+		end = strchr(p, ';');
+		if (end == NULL)
+			end = p + strlen(p);
+		if (end - p >= 12 && strncmp(p, "cmdline_url=", 12) == 0)
+			break;
+		if (*end == '\0')
+			return (NULL);
+		p = end + 1;
+	}
+	p += 12;
+	while (p < end) {
+		if (size == sizeof line - 1)
+			return (NULL);
+		ch = *p++;
+		if (ch == '%') {
+			if (end - p < 2 ||
+			    !isxdigit((u_char)p[0]) ||
+			    !isxdigit((u_char)p[1]))
+				return (NULL);
+			h[0] = p[0];
+			h[1] = p[1];
+
+			ch = strtoul(h, NULL, 16);
+			if (ch == '\0')
+				return (NULL);
+			p += 2;
+		}
+		line[size++] = ch;
+	}
+	line[size] = '\0';
+	return (clean_name(line, 1));
+}
+
 /* Fire an OSC 133 command event. */
 static void
 input_fire_command_event(struct window_pane *wp, const char *name)
@@ -3205,6 +3251,8 @@ input_fire_command_event(struct window_pane *wp, const char *name)
 	event_payload_set_window(ep, "window", wp->window);
 	event_payload_set_pane(ep, "pane", wp);
 
+	if (wp->cmd_line != NULL)
+		event_payload_set_string(ep, "command_line", "%s", wp->cmd_line);
 	if (wp->cmd_status != -1)
 		event_payload_set_int(ep, "command_status", wp->cmd_status);
 	if (tstart != 0)
@@ -3276,6 +3324,8 @@ input_osc_133(struct input_ctx *ictx, const char *p)
 			gl->osc133_data.out_start_col = s->cx;
 		}
 		if (wp != NULL) {
+			free(wp->cmd_line);
+			wp->cmd_line = input_osc_133_command_line(p);
 			wp->cmd_start_time = time(NULL);
 			wp->cmd_end_time = 0;
 			wp->flags |= PANE_CMDRUNNING;

tmux.1

@@ -1,4 +1,4 @@
-.\" $OpenBSD: tmux.1,v 1.1184 2026/10/12 12:35:03 nicm Exp $
+.\" $OpenBSD: tmux.1,v 1.1185 2026/10/13 10:21:58 nicm Exp $
 .\"
 .\" Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
 .\"
@@ -14,7 +14,7 @@
 .\" IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 .\" OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
 .\"
-.Dd $Mdocdate: October 12 2026 $
+.Dd $Mdocdate: October 13 2026 $
 .Dt TMUX 1
 .Os
 .Sh NAME
@@ -7445,6 +7445,7 @@ The following variables are available, where appropriate:
 .It Li "history_size" Ta "" Ta "Size of history in lines"
 .It Li "hook" Ta "" Ta "Name of running hook, if any"
 .It Li "hook_client" Ta "" Ta "Name of client where hook was run, if any"
+.It Li "hook_command_line" Ta "" Ta "Command line reported for an OSC 133 command hook, if any"
 .It Li "hook_fire_count" Ta "" Ta "Number of times hook has fired"
 .It Li "hook_fire_time" Ta "" Ta "Time hook last fired"
 .It Li "hook_last" Ta "" Ta "Previous value for a monitor hook"
@@ -7513,6 +7514,7 @@ The following variables are available, where appropriate:
 .It Li "pane_bottom" Ta "" Ta "Bottom of pane"
 .It Li "pane_command_duration" Ta "" Ta "Current or most recent OSC 133 command duration in seconds"
 .It Li "pane_command_end_time" Ta "" Ta "Time most recent OSC 133 command ended"
+.It Li "pane_command_line" Ta "" Ta "Current or most recent OSC 133 command line, if reported"
 .It Li "pane_command_running" Ta "" Ta "1 if an OSC 133 command is running"
 .It Li "pane_command_start_time" Ta "" Ta "Time current or most recent OSC 133 command started"
 .It Li "pane_command_status" Ta "" Ta "Exit status from most recent OSC 133 command"

tmux.h

@@ -1,4 +1,4 @@
-/* $OpenBSD: tmux.h,v 1.1458 2026/10/12 18:47:52 nicm Exp $ */
+/* $OpenBSD: tmux.h,v 1.1459 2026/10/13 10:21:58 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1355,6 +1355,7 @@ struct window_pane {
 	time_t		 cmd_start_time;
 	time_t		 cmd_end_time;
 	int		 cmd_status;
+	char		*cmd_line;
 
 	int		 fd;
 	struct bufferevent *event;

utf8.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: utf8.c,v 1.74 2026/10/05 08:32:24 nicm Exp $ */
+/* $OpenBSD: utf8.c,v 1.75 2026/10/13 10:21:58 nicm Exp $ */
 
 /*
  * Copyright (c) 2008 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -822,7 +822,7 @@ utf8_isvalid(const char *s)
 				continue;
 			return (0);
 		}
-		if (*s < 0x20 || *s > 0x7e)
+		if (*s != '\t' && *s != '\n' && (*s < 0x20 || *s > 0x7e))
 			return (0);
 		s++;
 	}

window.c

@@ -1,4 +1,4 @@
-/* $OpenBSD: window.c,v 1.385 2026/10/08 07:06:26 nicm Exp $ */
+/* $OpenBSD: window.c,v 1.386 2026/10/13 10:21:58 nicm Exp $ */
 
 /*
  * Copyright (c) 2007 Nicholas Marriott <nicholas.marriott@gmail.com>
@@ -1622,6 +1622,7 @@ window_pane_free(struct window_pane *wp)
 	log_debug("pane %%%u freed (%d references)", wp->id, wp->references);
 
 	free(wp->searchstr);
+	free(wp->cmd_line);
 	screen_free(&wp->status_screen);
 	screen_free(&wp->base);
 	free(wp->r.ranges);