diff --git a/cmd-new-session.c b/cmd-new-session.c
index df1ec45c..467fa879 100644
--- a/cmd-new-session.c
+++ b/cmd-new-session.c
@@ -21,9 +21,6 @@
 #include <string.h>
 #include <termios.h>
 
-#define TTYDEFCHARS
-#include <sys/ttydefaults.h>
-
 #include "tmux.h"
 
 /*
@@ -116,7 +113,7 @@ cmd_new_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 	struct session			*s;
 	struct window			*w;
 	struct environ			 env;
-	struct termios			 tio;
+	struct termios			 tio, *tiop;
 	const char			*update;
 	char				*overrides, *cmd, *cwd, *cause;
 	int				 detached, idx;
@@ -151,8 +148,8 @@ cmd_new_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 		detached = 1;
 
 	/*
-	 * Fill in the termios settings used for new windows in this session;
-	 * if there is a command client, use the control characters from it.
+	 * Save the termios settings, part of which is used for new windows in
+	 * this session.
 	 *
 	 * This is read again with tcgetattr() rather than using tty.tio as if
 	 * detached, tty_open won't be called. Because of this, it must be done
@@ -162,15 +159,9 @@ cmd_new_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 	if (ctx->cmdclient != NULL && ctx->cmdclient->tty.fd != -1) {
 		if (tcgetattr(ctx->cmdclient->tty.fd, &tio) != 0)
 			fatal("tcgetattr failed");
+		tiop = &tio;
 	} else
-		memcpy(tio.c_cc, ttydefchars, sizeof tio.c_cc);
-	tio.c_cc[VERASE] = '\177';
-	tio.c_iflag = TTYDEF_IFLAG;
-	tio.c_oflag = TTYDEF_OFLAG;
-	tio.c_lflag = TTYDEF_LFLAG;
-	tio.c_cflag = TTYDEF_CFLAG;
-	cfsetispeed(&tio, TTYDEF_SPEED);
-	cfsetospeed(&tio, TTYDEF_SPEED);
+		tiop = NULL;
 
 	/* Open the terminal if necessary. */
 	if (!detached && ctx->cmdclient != NULL) {
@@ -227,7 +218,7 @@ cmd_new_session_exec(struct cmd *self, struct cmd_ctx *ctx)
 	/* Create the new session. */
 	idx = -1 - options_get_number(&global_s_options, "base-index");
 	s = session_create(
-	    data->newname, cmd, cwd, &env, &tio, idx, sx, sy, &cause);
+	    data->newname, cmd, cwd, &env, tiop, idx, sx, sy, &cause);
 	if (s == NULL) {
 		ctx->error(ctx, "create session failed: %s", cause);
 		xfree(cause);
diff --git a/cmd-respawn-window.c b/cmd-respawn-window.c
index cd96f50b..540931aa 100644
--- a/cmd-respawn-window.c
+++ b/cmd-respawn-window.c
@@ -76,7 +76,7 @@ cmd_respawn_window_exec(struct cmd *self, struct cmd_ctx *ctx)
 	TAILQ_INSERT_HEAD(&w->panes, wp, entry);
 	window_pane_resize(wp, w->sx, w->sy);
 	if (window_pane_spawn(
-	    wp, data->arg, NULL, NULL, &env, &s->tio, &cause) != 0) {
+	    wp, data->arg, NULL, NULL, &env, s->tio, &cause) != 0) {
 		ctx->error(ctx, "respawn window failed: %s", cause);
 		xfree(cause);
 		environ_free(&env);
diff --git a/cmd-split-window.c b/cmd-split-window.c
index d6fc3f78..1604d9e2 100644
--- a/cmd-split-window.c
+++ b/cmd-split-window.c
@@ -190,7 +190,7 @@ cmd_split_window_exec(struct cmd *self, struct cmd_ctx *ctx)
 		shell = _PATH_BSHELL;
 
 	wp = window_add_pane(w, hlimit);
-	if (window_pane_spawn(wp, cmd, shell, cwd, &env, &s->tio, &cause) != 0)
+	if (window_pane_spawn(wp, cmd, shell, cwd, &env, s->tio, &cause) != 0)
 		goto error;
 	if (layout_split_pane(w->active, type, size, wp) != 0) {
 		cause = xstrdup("pane too small");
diff --git a/session.c b/session.c
index 4e5ac83e..fd2345b3 100644
--- a/session.c
+++ b/session.c
@@ -139,7 +139,12 @@ session_create(const char *name, const char *cmd, const char *cwd,
 	environ_init(&s->environ);
 	if (env != NULL)
 		environ_copy(env, &s->environ);
-	memcpy(&s->tio, tio, sizeof s->tio);
+
+	s->tio = NULL;
+	if (tio != NULL) {
+		s->tio = xmalloc(sizeof *s->tio);
+		memcpy(s->tio, tio, sizeof *s->tio);
+	}
 
 	s->sx = sx;
 	s->sy = sy;
@@ -182,6 +187,9 @@ session_destroy(struct session *s)
 	while (!ARRAY_EMPTY(&sessions) && ARRAY_LAST(&sessions) == NULL)
 		ARRAY_TRUNC(&sessions, 1);
 
+	if (s->tio != NULL)
+		xfree(s->tio);
+
 	session_alert_cancel(s, NULL);
 	environ_free(&s->environ);
 	options_free(&s->options);
@@ -237,7 +245,7 @@ session_new(struct session *s,
 
 	hlimit = options_get_number(&s->options, "history-limit");
 	w = window_create(
-	    name, cmd, shell, cwd, &env, &s->tio, s->sx, s->sy, hlimit, cause);
+	    name, cmd, shell, cwd, &env, s->tio, s->sx, s->sy, hlimit, cause);
 	if (w == NULL) {
 		environ_free(&env);
 		return (NULL);
diff --git a/tmux.h b/tmux.h
index 63f75577..0c5d2686 100644
--- a/tmux.h
+++ b/tmux.h
@@ -815,7 +815,7 @@ struct session {
 #define SESSION_DEAD 0x2
 	int		 flags;
 
-	struct termios   tio;
+	struct termios	*tio;
 
 	struct environ	 environ;
 
diff --git a/window.c b/window.c
index 62b1f487..5683f174 100644
--- a/window.c
+++ b/window.c
@@ -454,6 +454,7 @@ window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
 	struct environ_entry	*envent;
 	const char		*ptr;
 	struct timeval	 	 tv;
+	struct termios		 tio2;
 	u_int		 	 i;
 
 	if (wp->fd != -1)
@@ -484,7 +485,7 @@ window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
 	tv.tv_usec = NAME_INTERVAL * 1000L;
 	timeradd(&wp->window->name_timer, &tv, &wp->window->name_timer);
 
- 	switch (wp->pid = forkpty(&wp->fd, wp->tty, tio, &ws)) {
+ 	switch (wp->pid = forkpty(&wp->fd, wp->tty, NULL, &ws)) {
 	case -1:
 		wp->fd = -1;
 		xasprintf(cause, "%s: %s", cmd, strerror(errno));
@@ -493,6 +494,14 @@ window_pane_spawn(struct window_pane *wp, const char *cmd, const char *shell,
 		if (chdir(wp->cwd) != 0)
 			chdir("/");
 
+		if (tcgetattr(STDIN_FILENO, &tio2) != 0)
+			fatal("tcgetattr failed");
+		if (tio != NULL)
+			memcpy(tio2.c_cc, tio->c_cc, sizeof tio2.c_cc);
+		tio2.c_cc[VERASE] = '\177';
+		if (tcsetattr(STDIN_FILENO, TCSANOW, &tio2) != 0)
+			fatal("tcgetattr failed");
+
 		ARRAY_INIT(&varlist);
 		for (varp = environ; *varp != NULL; varp++) {
 			var = xstrdup(*varp);