From 4ec61bef461aba6d5849bce971a241850b8d7ef6 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 20:40:51 +0000
Subject: [PATCH 01/15] Fix usage of detach-client.

---
 cmd-detach-client.c | 2 +-
 tmux.1              | 3 +--
 2 files changed, 2 insertions(+), 3 deletions(-)

diff --git a/cmd-detach-client.c b/cmd-detach-client.c
index 813ac032..f7369df0 100644
--- a/cmd-detach-client.c
+++ b/cmd-detach-client.c
@@ -31,7 +31,7 @@ enum cmd_retval	 cmd_detach_client_exec(struct cmd *, struct cmd_q *);
 const struct cmd_entry cmd_detach_client_entry = {
 	"detach-client", "detach",
 	"as:t:P", 0, 0,
-	"[-P] [-a] [-s target-session] " CMD_TARGET_CLIENT_USAGE,
+	"[-aP] [-s target-session] " CMD_TARGET_CLIENT_USAGE,
 	CMD_READONLY,
 	cmd_detach_client_exec
 };
diff --git a/tmux.1 b/tmux.1
index 3fd383d6..455de33b 100644
--- a/tmux.1
+++ b/tmux.1
@@ -714,8 +714,7 @@ is used,
 .Ic update-environment
 option will not be applied.
 .It Xo Ic detach-client
-.Op Fl P
-.Op Fl a
+.Op Fl aP
 .Op Fl s Ar target-session
 .Op Fl t Ar target-client
 .Xc

From 9cccb8c1159b0a4747b5152e2df08e42207b574d Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 21:19:46 +0000
Subject: [PATCH 02/15] Make the log stuff a bit tidier with some helper
 functions.

---
 cmd-show-messages.c |  1 -
 log.c               | 35 +++++++++++++++++++++++++++++------
 proc.c              |  2 +-
 server.c            |  2 +-
 tmux.c              | 15 +--------------
 tmux.h              |  8 ++++----
 6 files changed, 36 insertions(+), 27 deletions(-)

diff --git a/cmd-show-messages.c b/cmd-show-messages.c
index 92ac5cc2..3d2edf9a 100644
--- a/cmd-show-messages.c
+++ b/cmd-show-messages.c
@@ -61,7 +61,6 @@ cmd_show_messages_server(struct cmd_q *cmdq)
 
 	cmdq_print(cmdq, "started %s", tim);
 	cmdq_print(cmdq, "socket path %s", socket_path);
-	cmdq_print(cmdq, "debug level %d", debug_level);
 	cmdq_print(cmdq, "protocol version %d", PROTOCOL_VERSION);
 
 	return (1);
diff --git a/log.c b/log.c
index 6c7be8b2..46f1673c 100644
--- a/log.c
+++ b/log.c
@@ -22,30 +22,53 @@
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <unistd.h>
 #include <vis.h>
 
 #include "tmux.h"
 
-FILE	*log_file;
+static FILE	*log_file;
+static int	 log_level;
 
-void	 log_event_cb(int, const char *);
-void	 log_vwrite(const char *, va_list);
+static void	 log_event_cb(int, const char *);
+static void	 log_vwrite(const char *, va_list);
 
 /* Log callback for libevent. */
-void
+static void
 log_event_cb(__unused int severity, const char *msg)
 {
 	log_debug("%s", msg);
 }
 
+/* Increment log level. */
+void
+log_add_level(void)
+{
+	log_level++;
+}
+
+/* Get log level. */
+int
+log_get_level(void)
+{
+	return (log_level);
+}
+
 /* Open logging to file. */
 void
-log_open(const char *path)
+log_open(const char *name)
 {
+	char	*path;
+
+	if (log_level == 0)
+		return;
+
 	if (log_file != NULL)
 		fclose(log_file);
 
+	xasprintf(&path, "tmux-%s-%ld.log", name, (long)getpid());
 	log_file = fopen(path, "w");
+	free(path);
 	if (log_file == NULL)
 		return;
 
@@ -65,7 +88,7 @@ log_close(void)
 }
 
 /* Write a log message. */
-void
+static void
 log_vwrite(const char *msg, va_list ap)
 {
 	char		*fmt, *out;
diff --git a/proc.c b/proc.c
index 31fd136b..06340cd9 100644
--- a/proc.c
+++ b/proc.c
@@ -188,7 +188,7 @@ proc_start(const char *name, struct event_base *base, int forkflag,
 			fatalx("event_reinit failed");
 	}
 
-	logfile(name);
+	log_open(name);
 	setproctitle("%s (%s)", name, socket_path);
 
 	log_debug("%s started (%ld): socket %s, protocol %d", name,
diff --git a/server.c b/server.c
index e17b9356..e9159422 100644
--- a/server.c
+++ b/server.c
@@ -173,7 +173,7 @@ server_start(struct event_base *base, int lockfd, char *lockfile)
 	}
 	close(pair[0]);
 
-	if (debug_level > 3)
+	if (log_get_level() > 3)
 		tty_create_log();
 	if (pledge("stdio rpath wpath cpath fattr unix getpw recvfd proc exec "
 	    "tty ps", NULL) != 0)
diff --git a/tmux.c b/tmux.c
index aa827178..f5383fcf 100644
--- a/tmux.c
+++ b/tmux.c
@@ -44,7 +44,6 @@ struct options	*global_w_options;	/* window options */
 struct environ	*global_environ;
 
 char		*shell_cmd;
-int		 debug_level;
 time_t		 start_time;
 char		 socket_path[PATH_MAX];
 
@@ -61,18 +60,6 @@ usage(void)
 	exit(1);
 }
 
-void
-logfile(const char *name)
-{
-	char	*path;
-
-	if (debug_level > 0) {
-		xasprintf(&path, "tmux-%s-%ld.log", name, (long) getpid());
-		log_open(path);
-		free(path);
-	}
-}
-
 const char *
 getshell(void)
 {
@@ -243,7 +230,7 @@ main(int argc, char **argv)
 			flags |= CLIENT_UTF8;
 			break;
 		case 'v':
-			debug_level++;
+			log_add_level();
 			break;
 		default:
 			usage();
diff --git a/tmux.h b/tmux.h
index 591fe54e..5f469f92 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1432,10 +1432,8 @@ extern struct options *global_s_options;
 extern struct options *global_w_options;
 extern struct environ *global_environ;
 extern char	*shell_cmd;
-extern int	 debug_level;
 extern time_t	 start_time;
 extern char	 socket_path[PATH_MAX];
-void		 logfile(const char *);
 const char	*getshell(void);
 int		 checkshell(const char *);
 int		 areshell(const char *);
@@ -2210,8 +2208,10 @@ char		*utf8_padcstr(const char *, u_int);
 char   *get_proc_name(int, char *);
 
 /* log.c */
-void		 log_open(const char *);
-void		 log_close(void);
+void	log_add_level(void);
+int	log_get_level(void);
+void	log_open(const char *);
+void	log_close(void);
 void printflike(1, 2) log_debug(const char *, ...);
 __dead void printflike(1, 2) fatal(const char *, ...);
 __dead void printflike(1, 2) fatalx(const char *, ...);

From bdbbd9711c05507161bc70ccdde91bdb719d943b Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 21:23:44 +0000
Subject: [PATCH 03/15] Show libevent version in showmsgs -I.

---
 cmd-show-messages.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/cmd-show-messages.c b/cmd-show-messages.c
index 3d2edf9a..8cf71f41 100644
--- a/cmd-show-messages.c
+++ b/cmd-show-messages.c
@@ -62,6 +62,8 @@ cmd_show_messages_server(struct cmd_q *cmdq)
 	cmdq_print(cmdq, "started %s", tim);
 	cmdq_print(cmdq, "socket path %s", socket_path);
 	cmdq_print(cmdq, "protocol version %d", PROTOCOL_VERSION);
+	cmdq_print(cmdq, "libevent %s (%s)", event_get_version(),
+	    event_get_method());
 
 	return (1);
 }

From 4e3015a8925f72b35393afec250cc46e4f480641 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 21:32:36 +0000
Subject: [PATCH 04/15] Log some system and libevent information at startup.

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

diff --git a/proc.c b/proc.c
index 06340cd9..593c1b8b 100644
--- a/proc.c
+++ b/proc.c
@@ -19,6 +19,7 @@
 #include <sys/types.h>
 #include <sys/queue.h>
 #include <sys/uio.h>
+#include <sys/utsname.h>
 
 #include <errno.h>
 #include <event.h>
@@ -170,6 +171,7 @@ proc_start(const char *name, struct event_base *base, int forkflag,
     void (*signalcb)(int))
 {
 	struct tmuxproc	*tp;
+	struct utsname	 u;
 
 	if (forkflag) {
 		switch (fork()) {
@@ -191,8 +193,13 @@ proc_start(const char *name, struct event_base *base, int forkflag,
 	log_open(name);
 	setproctitle("%s (%s)", name, socket_path);
 
+	if (uname(&u) < 0)
+		memset(&u, 0, sizeof u);
+
 	log_debug("%s started (%ld): socket %s, protocol %d", name,
 	    (long)getpid(), socket_path, PROTOCOL_VERSION);
+	log_debug("on %s %s %s; libevent %s (%s)", u.sysname, u.release,
+	    u.version, event_get_version(), event_get_method());
 
 	tp = xcalloc(1, sizeof *tp);
 	tp->name = xstrdup(name);

From 9fd3318dd818c45432581beff5b1a5f6cb55f2ff Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 21:50:06 +0000
Subject: [PATCH 05/15] All kill-session -C to clear alerts in all windows,
 suggested by Aaron U'Ren.

---
 cmd-kill-session.c | 13 ++++++++++---
 1 file changed, 10 insertions(+), 3 deletions(-)

diff --git a/cmd-kill-session.c b/cmd-kill-session.c
index 74843eb6..3f39c241 100644
--- a/cmd-kill-session.c
+++ b/cmd-kill-session.c
@@ -31,8 +31,8 @@ enum cmd_retval	 cmd_kill_session_exec(struct cmd *, struct cmd_q *);
 
 const struct cmd_entry cmd_kill_session_entry = {
 	"kill-session", NULL,
-	"at:", 0, 0,
-	"[-a] " CMD_TARGET_SESSION_USAGE,
+	"aCt:", 0, 0,
+	"[-aC] " CMD_TARGET_SESSION_USAGE,
 	0,
 	cmd_kill_session_exec
 };
@@ -42,11 +42,18 @@ cmd_kill_session_exec(struct cmd *self, struct cmd_q *cmdq)
 {
 	struct args	*args = self->args;
 	struct session	*s, *sloop, *stmp;
+	struct winlink	*wl;
 
 	if ((s = cmd_find_session(cmdq, args_get(args, 't'), 0)) == NULL)
 		return (CMD_RETURN_ERROR);
 
-	if (args_has(args, 'a')) {
+	if (args_has(args, 'C')) {
+		RB_FOREACH(wl, winlinks, &s->windows) {
+			wl->window->flags &= ~WINDOW_ALERTFLAGS;
+			wl->flags &= ~WINLINK_ALERTFLAGS;
+		}
+		server_redraw_session(s);
+	} else if (args_has(args, 'a')) {
 		RB_FOREACH_SAFE(sloop, sessions, &sessions, stmp) {
 			if (sloop != s) {
 				server_destroy_session(sloop);

From 1e2df2d46496fc025330c25fa08e83d14e62d11b Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 21:52:06 +0000
Subject: [PATCH 06/15] Remove the -I part of show-messages which isn't really
 that useful; the server start time can now be accessed with a new start_time
 format (use: tmux display -p '#{t:start_time}')

---
 cmd-show-messages.c | 26 ++------------------------
 format.c            |  2 ++
 server.c            |  2 +-
 tmux.1              | 12 ++++++++----
 tmux.c              |  2 +-
 tmux.h              |  6 +++---
 6 files changed, 17 insertions(+), 33 deletions(-)

diff --git a/cmd-show-messages.c b/cmd-show-messages.c
index 8cf71f41..c98c2c91 100644
--- a/cmd-show-messages.c
+++ b/cmd-show-messages.c
@@ -33,8 +33,8 @@ enum cmd_retval	 cmd_show_messages_exec(struct cmd *, struct cmd_q *);
 
 const struct cmd_entry cmd_show_messages_entry = {
 	"show-messages", "showmsgs",
-	"IJTt:", 0, 0,
-	"[-IJT] " CMD_TARGET_CLIENT_USAGE,
+	"JTt:", 0, 0,
+	"[-JT] " CMD_TARGET_CLIENT_USAGE,
 	0,
 	cmd_show_messages_exec
 };
@@ -47,27 +47,9 @@ const struct cmd_entry cmd_server_info_entry = {
 	cmd_show_messages_exec
 };
 
-int	cmd_show_messages_server(struct cmd_q *);
 int	cmd_show_messages_terminals(struct cmd_q *, int);
 int	cmd_show_messages_jobs(struct cmd_q *, int);
 
-int
-cmd_show_messages_server(struct cmd_q *cmdq)
-{
-	char	*tim;
-
-	tim = ctime(&start_time);
-	*strchr(tim, '\n') = '\0';
-
-	cmdq_print(cmdq, "started %s", tim);
-	cmdq_print(cmdq, "socket path %s", socket_path);
-	cmdq_print(cmdq, "protocol version %d", PROTOCOL_VERSION);
-	cmdq_print(cmdq, "libevent %s (%s)", event_get_version(),
-	    event_get_method());
-
-	return (1);
-}
-
 int
 cmd_show_messages_terminals(struct cmd_q *cmdq, int blank)
 {
@@ -118,10 +100,6 @@ cmd_show_messages_exec(struct cmd *self, struct cmd_q *cmdq)
 	int			 done, blank;
 
 	done = blank = 0;
-	if (args_has(args, 'I') || self->entry == &cmd_server_info_entry) {
-		blank = cmd_show_messages_server(cmdq);
-		done = 1;
-	}
 	if (args_has(args, 'T') || self->entry == &cmd_server_info_entry) {
 		blank = cmd_show_messages_terminals(cmdq, blank);
 		done = 1;
diff --git a/format.c b/format.c
index 50fa7dea..bafd8ce6 100644
--- a/format.c
+++ b/format.c
@@ -488,6 +488,8 @@ format_create_flags(int flags)
 	format_add_cb(ft, "host", format_cb_host);
 	format_add_cb(ft, "host_short", format_cb_host_short);
 	format_add_cb(ft, "pid", format_cb_pid);
+	format_add(ft, "socket_path", "%s", socket_path);
+	format_add_tv(ft, "start_time", &start_time);
 
 	return (ft);
 }
diff --git a/server.c b/server.c
index e9159422..d950ed77 100644
--- a/server.c
+++ b/server.c
@@ -187,7 +187,7 @@ server_start(struct event_base *base, int lockfd, char *lockfile)
 	mode_key_init_trees();
 	key_bindings_init();
 
-	start_time = time(NULL);
+	gettimeofday(&start_time, NULL);
 
 	server_fd = server_create_socket();
 	if (server_fd == -1)
diff --git a/tmux.1 b/tmux.1
index 455de33b..cba38264 100644
--- a/tmux.1
+++ b/tmux.1
@@ -740,7 +740,7 @@ Kill the
 .Nm
 server and clients and destroy all sessions.
 .It Xo Ic kill-session
-.Op Fl a
+.Op Fl aC
 .Op Fl t Ar target-session
 .Xc
 Destroy the given session, closing any windows linked to it and no other
@@ -748,6 +748,10 @@ sessions, and detaching all clients attached to it.
 If
 .Fl a
 is given, all sessions but the specified one is killed.
+The
+.Fl C
+clears alerts (bell, activity, or silence) in all windows linked to the
+session.
 .It Xo Ic list-clients
 .Op Fl F Ar format
 .Op Fl t Ar target-session
@@ -887,7 +891,7 @@ is specified, only update the client's status bar.
 Rename the session to
 .Ar new-name .
 .It Xo Ic show-messages
-.Op Fl IJT
+.Op Fl JT
 .Op Fl t Ar target-client
 .Xc
 .D1 (alias: Ic showmsgs )
@@ -900,11 +904,10 @@ With
 .Fl t ,
 display the log for
 .Ar target-client .
-.Fl I ,
 .Fl J
 and
 .Fl T
-show debugging information about the running server, jobs and terminals.
+show debugging information about jobs and terminals.
 .It Ic source-file Ar path
 .D1 (alias: Ic source )
 Execute commands from
@@ -3410,6 +3413,7 @@ The following variables are available, where appropriate:
 .It Li "session_name" Ta "#S" Ta "Name of session"
 .It Li "session_width" Ta "" Ta "Width of session"
 .It Li "session_windows" Ta "" Ta "Number of windows in session"
+.It Li "start_time" Ta "" Ta "Server start time"
 .It Li "window_activity" Ta "" Ta "Integer time of window last activity"
 .It Li "window_active" Ta "" Ta "1 if window active"
 .It Li "window_bell_flag" Ta "" Ta "1 if window has bell"
diff --git a/tmux.c b/tmux.c
index f5383fcf..7e89d526 100644
--- a/tmux.c
+++ b/tmux.c
@@ -44,7 +44,7 @@ struct options	*global_w_options;	/* window options */
 struct environ	*global_environ;
 
 char		*shell_cmd;
-time_t		 start_time;
+struct timeval	 start_time;
 char		 socket_path[PATH_MAX];
 
 __dead void	 usage(void);
diff --git a/tmux.h b/tmux.h
index 5f469f92..97908d98 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1431,9 +1431,9 @@ extern struct options *global_options;
 extern struct options *global_s_options;
 extern struct options *global_w_options;
 extern struct environ *global_environ;
-extern char	*shell_cmd;
-extern time_t	 start_time;
-extern char	 socket_path[PATH_MAX];
+extern char		*shell_cmd;
+extern struct timeval	 start_time;
+extern char		 socket_path[PATH_MAX];
 const char	*getshell(void);
 int		 checkshell(const char *);
 int		 areshell(const char *);

From bef217b241ec50d6aed87dbb3604acd1bdb74121 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 22:04:36 +0000
Subject: [PATCH 07/15] Switch a fprintf to a fatal, and wrap some long lines.

---
 client.c | 15 +++++++--------
 1 file changed, 7 insertions(+), 8 deletions(-)

diff --git a/client.c b/client.c
index 53a98a30..fcb704fb 100644
--- a/client.c
+++ b/client.c
@@ -303,11 +303,8 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 	event_set(&client_stdin, STDIN_FILENO, EV_READ|EV_PERSIST,
 	    client_stdin_callback, NULL);
 	if (client_flags & CLIENT_CONTROLCONTROL) {
-		if (tcgetattr(STDIN_FILENO, &saved_tio) != 0) {
-			fprintf(stderr, "tcgetattr failed: %s\n",
-			    strerror(errno));
-			return (1);
-		}
+		if (tcgetattr(STDIN_FILENO, &saved_tio) != 0)
+			fatal("tcgetattr failed");
 		cfmakeraw(&tio);
 		tio.c_iflag = ICRNL|IXANY;
 		tio.c_oflag = OPOST|ONLCR;
@@ -389,7 +386,8 @@ client_send_identify(const char *ttynam, const char *cwd)
 		s = "";
 	proc_send(client_peer, MSG_IDENTIFY_TERM, -1, s, strlen(s) + 1);
 
-	proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam, strlen(ttynam) + 1);
+	proc_send(client_peer, MSG_IDENTIFY_TTYNAME, -1, ttynam,
+	    strlen(ttynam) + 1);
 	proc_send(client_peer, MSG_IDENTIFY_CWD, -1, cwd, strlen(cwd) + 1);
 
 	if ((fd = dup(STDIN_FILENO)) == -1)
@@ -401,8 +399,9 @@ client_send_identify(const char *ttynam, const char *cwd)
 
 	for (ss = environ; *ss != NULL; ss++) {
 		sslen = strlen(*ss) + 1;
-		if (sslen <= MAX_IMSGSIZE - IMSG_HEADER_SIZE)
-			proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen);
+		if (sslen > MAX_IMSGSIZE - IMSG_HEADER_SIZE)
+			continue;
+		proc_send(client_peer, MSG_IDENTIFY_ENVIRON, -1, *ss, sslen);
 	}
 
 	proc_send(client_peer, MSG_IDENTIFY_DONE, -1, NULL, 0);

From 8976dac9e0c2e55b240ad55f4f7fa0a3b887c0e2 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 22:09:53 +0000
Subject: [PATCH 08/15] Remove malloc_options DEBUG bit.

---
 tmux.c | 8 --------
 1 file changed, 8 deletions(-)

diff --git a/tmux.c b/tmux.c
index 7e89d526..c515ebb2 100644
--- a/tmux.c
+++ b/tmux.c
@@ -34,10 +34,6 @@
 
 #include "tmux.h"
 
-#ifdef DEBUG
-extern char	*malloc_options;
-#endif
-
 struct options	*global_options;	/* server options */
 struct options	*global_s_options;	/* session options */
 struct options	*global_w_options;	/* window options */
@@ -182,10 +178,6 @@ main(int argc, char **argv)
 	const char	*s;
 	int		 opt, flags, keys;
 
-#ifdef DEBUG
-	malloc_options = (char *) "AFGJPX";
-#endif
-
 	setlocale(LC_TIME, "");
 	tzset();
 

From c913fb99b6f0f7d08b77d8d021df7d7fa27f82d0 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 22:27:22 +0000
Subject: [PATCH 09/15] Tidy the code that works out the socket path, and just
 use the full path in the global socket_path rather than copying it.

---
 client.c |  4 +--
 tmux.c   | 86 +++++++++++++++++++++++++-------------------------------
 tmux.h   |  2 +-
 3 files changed, 42 insertions(+), 50 deletions(-)

diff --git a/client.c b/client.c
index fcb704fb..595aff9b 100644
--- a/client.c
+++ b/client.c
@@ -55,7 +55,7 @@ int		 client_attached;
 
 __dead void	client_exec(const char *);
 int		client_get_lock(char *);
-int		client_connect(struct event_base *, char *, int);
+int		client_connect(struct event_base *, const char *, int);
 void		client_send_identify(const char *, const char *);
 void		client_stdin_callback(int, short, void *);
 void		client_write(int, const char *, size_t);
@@ -96,7 +96,7 @@ client_get_lock(char *lockfile)
 
 /* Connect client to server. */
 int
-client_connect(struct event_base *base, char *path, int start_server)
+client_connect(struct event_base *base, const char *path, int start_server)
 {
 	struct sockaddr_un	sa;
 	size_t			size;
diff --git a/tmux.c b/tmux.c
index c515ebb2..f2143755 100644
--- a/tmux.c
+++ b/tmux.c
@@ -41,10 +41,10 @@ struct environ	*global_environ;
 
 char		*shell_cmd;
 struct timeval	 start_time;
-char		 socket_path[PATH_MAX];
+const char	*socket_path;
 
 __dead void	 usage(void);
-char 		*makesocketpath(const char *);
+static char	*make_label(const char *);
 
 __dead void
 usage(void)
@@ -102,38 +102,48 @@ areshell(const char *shell)
 	return (0);
 }
 
-char *
-makesocketpath(const char *label)
+static char *
+make_label(const char *label)
 {
-	char		base[PATH_MAX], realbase[PATH_MAX], *path, *s;
-	struct stat	sb;
-	u_int		uid;
+	char		*base, resolved[PATH_MAX], *path, *s;
+	struct stat	 sb;
+	u_int		 uid;
+	int		 saved_errno;
+
+	if (label == NULL)
+		label = "default";
 
 	uid = getuid();
+
 	if ((s = getenv("TMUX_TMPDIR")) != NULL && *s != '\0')
-		xsnprintf(base, sizeof base, "%s/tmux-%u", s, uid);
+		xasprintf(&base, "%s/tmux-%u", s, uid);
 	else
-		xsnprintf(base, sizeof base, "%s/tmux-%u", _PATH_TMP, uid);
+		xasprintf(&base, "%s/tmux-%u", _PATH_TMP, uid);
 
 	if (mkdir(base, S_IRWXU) != 0 && errno != EEXIST)
-		return (NULL);
+		goto fail;
 
 	if (lstat(base, &sb) != 0)
-		return (NULL);
+		goto fail;
 	if (!S_ISDIR(sb.st_mode)) {
 		errno = ENOTDIR;
-		return (NULL);
+		goto fail;
 	}
 	if (sb.st_uid != uid || (sb.st_mode & S_IRWXO) != 0) {
 		errno = EACCES;
-		return (NULL);
+		goto fail;
 	}
 
-	if (realpath(base, realbase) == NULL)
-		strlcpy(realbase, base, sizeof realbase);
-
-	xasprintf(&path, "%s/%s", realbase, label);
+	if (realpath(base, resolved) == NULL)
+		strlcpy(resolved, base, sizeof resolved);
+	xasprintf(&path, "%s/%s", resolved, label);
 	return (path);
+
+fail:
+	saved_errno = errno;
+	free(base);
+	errno = saved_errno;
+	return (NULL);
 }
 
 void
@@ -289,41 +299,23 @@ main(int argc, char **argv)
 	}
 
 	/*
-	 * Figure out the socket path. If specified on the command-line with -S
-	 * or -L, use it, otherwise try $TMUX or assume -L default.
+	 * If socket is specified on the command-line with -S or -L, it is
+	 * used. Otherwise, $TMUX is checked and if that fails "default" is
+	 * used.
 	 */
-	if (path == NULL) {
-		/* If no -L, use the environment. */
-		if (label == NULL) {
-			s = getenv("TMUX");
-			if (s != NULL) {
-				path = xstrdup(s);
-				path[strcspn (path, ",")] = '\0';
-				if (*path == '\0') {
-					free(path);
-					label = xstrdup("default");
-				}
-			} else
-				label = xstrdup("default");
-		}
-
-		/* -L or default set. */
-		if (label != NULL) {
-			if ((path = makesocketpath(label)) == NULL) {
-				fprintf(stderr, "can't create socket: %s\n",
-				    strerror(errno));
-				exit(1);
-			}
+	if (path == NULL && label == NULL) {
+		s = getenv("TMUX");
+		if (s != NULL && *s != '\0' && *s != ',') {
+			path = xstrdup(s);
+			path[strcspn (path, ",")] = '\0';
 		}
 	}
-	free(label);
-
-	if (strlcpy(socket_path, path, sizeof socket_path) >=
-	    sizeof socket_path) {
-		fprintf(stderr, "socket path too long: %s\n", path);
+	if (path == NULL && (path = make_label(label)) == NULL) {
+		fprintf(stderr, "can't create socket: %s\n", strerror(errno));
 		exit(1);
 	}
-	free(path);
+	socket_path = path;
+	free(label);
 
 	/* Pass control to the client. */
 	exit(client_main(event_init(), argc, argv, flags));
diff --git a/tmux.h b/tmux.h
index 97908d98..50d7fb03 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1433,7 +1433,7 @@ extern struct options *global_w_options;
 extern struct environ *global_environ;
 extern char		*shell_cmd;
 extern struct timeval	 start_time;
-extern char		 socket_path[PATH_MAX];
+extern const char	*socket_path;
 const char	*getshell(void);
 int		 checkshell(const char *);
 int		 areshell(const char *);

From c18fbefe93dfbc7525b27e0129f8a0e8e9b70117 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 22:27:59 +0000
Subject: [PATCH 10/15] Document socket_path format.

---
 tmux.1 | 1 +
 1 file changed, 1 insertion(+)

diff --git a/tmux.1 b/tmux.1
index cba38264..8fa6ad55 100644
--- a/tmux.1
+++ b/tmux.1
@@ -3413,6 +3413,7 @@ The following variables are available, where appropriate:
 .It Li "session_name" Ta "#S" Ta "Name of session"
 .It Li "session_width" Ta "" Ta "Width of session"
 .It Li "session_windows" Ta "" Ta "Number of windows in session"
+.It Li "socket_path" Ta "" "Server socket path"
 .It Li "start_time" Ta "" Ta "Server start time"
 .It Li "window_activity" Ta "" Ta "Integer time of window last activity"
 .It Li "window_active" Ta "" Ta "1 if window active"

From 73e30cbda8ade3a1c7ba3b771a911545826f76b7 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 22:45:44 +0000
Subject: [PATCH 11/15] Actually show something (even if it not that helpful)
 if the server fails to start (for example if it can't create the socket),
 rather than hanging or showing nothing.

---
 client.c | 27 ++++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/client.c b/client.c
index 595aff9b..5fdfd029 100644
--- a/client.c
+++ b/client.c
@@ -76,8 +76,12 @@ client_get_lock(char *lockfile)
 {
 	int lockfd;
 
-	if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1)
-		fatal("open failed");
+	if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1) {
+		lockfd = open("/dev/null", O_WRONLY);
+		if (lockfd == -1)
+			fatal("open failed");
+		return (lockfd);
+	}
 	log_debug("lock file is %s", lockfile);
 
 	if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) {
@@ -114,10 +118,10 @@ client_connect(struct event_base *base, const char *path, int start_server)
 
 retry:
 	if ((fd = socket(AF_UNIX, SOCK_STREAM, 0)) == -1)
-		fatal("socket failed");
+		return (-1);
 
 	log_debug("trying connect");
-	if (connect(fd, (struct sockaddr *) &sa, sizeof(sa)) == -1) {
+	if (connect(fd, (struct sockaddr *)&sa, sizeof sa) == -1) {
 		log_debug("connect failed: %s", strerror(errno));
 		if (errno != ECONNREFUSED && errno != ENOENT)
 			goto failed;
@@ -255,6 +259,9 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 		cmd_list_free(cmdlist);
 	}
 
+	/* Create client process structure (starts logging). */
+	client_proc = proc_start("client", base, 0, client_signal);
+
 	/* Initialize the client socket and start the server. */
 	fd = client_connect(base, socket_path, cmdflags & CMD_STARTSERVER);
 	if (fd == -1) {
@@ -267,9 +274,6 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 		}
 		return (1);
 	}
-
-	/* Build process state. */
-	client_proc = proc_start("client", base, 0, client_signal);
 	client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL);
 
 	/* Save these before pledge(). */
@@ -365,7 +369,8 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 			printf("%%exit\n");
 		printf("\033\\");
 		tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio);
-	}
+	} else
+		fprintf(stderr, "%s\n", client_exit_message());
 	setblocking(STDIN_FILENO, 1);
 	return (client_exitval);
 }
@@ -517,7 +522,11 @@ client_dispatch(struct imsg *imsg, __unused void *arg)
 	if (imsg == NULL) {
 		client_exitreason = CLIENT_EXIT_LOST_SERVER;
 		client_exitval = 1;
-	} else if (client_attached)
+		proc_exit(client_proc);
+		return;
+	}
+
+	if (client_attached)
 		client_dispatch_attached(imsg);
 	else
 		client_dispatch_wait(imsg);

From dca93c56e05ce631dd2f80da759f40c4d4b20ab5 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 23:01:51 +0000
Subject: [PATCH 12/15] Do lock failures slightly better, return a special
 value so we don't unlink the wrong thing.

---
 client.c | 34 ++++++++++++++++++----------------
 server.c |  8 +++++---
 2 files changed, 23 insertions(+), 19 deletions(-)

diff --git a/client.c b/client.c
index 5fdfd029..8144dd1c 100644
--- a/client.c
+++ b/client.c
@@ -67,23 +67,21 @@ const char     *client_exit_message(void);
 
 /*
  * Get server create lock. If already held then server start is happening in
- * another client, so block until the lock is released and return -1 to
- * retry. Ignore other errors - just continue and start the server without the
- * lock.
+ * another client, so block until the lock is released and return -2 to
+ * retry. Return -1 on failure to continue and start the server anyway.
  */
 int
 client_get_lock(char *lockfile)
 {
 	int lockfd;
 
-	if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1) {
-		lockfd = open("/dev/null", O_WRONLY);
-		if (lockfd == -1)
-			fatal("open failed");
-		return (lockfd);
-	}
 	log_debug("lock file is %s", lockfile);
 
+	if ((lockfd = open(lockfile, O_WRONLY|O_CREAT, 0600)) == -1) {
+		log_debug("open failed: %s", strerror(errno));
+		return (-1);
+	}
+
 	if (flock(lockfd, LOCK_EX|LOCK_NB) == -1) {
 		log_debug("flock failed: %s", strerror(errno));
 		if (errno != EAGAIN)
@@ -91,7 +89,7 @@ client_get_lock(char *lockfile)
 		while (flock(lockfd, LOCK_EX) == -1 && errno == EINTR)
 			/* nothing */;
 		close(lockfd);
-		return (-1);
+		return (-2);
 	}
 	log_debug("flock succeeded");
 
@@ -131,12 +129,16 @@ retry:
 
 		if (!locked) {
 			xasprintf(&lockfile, "%s.lock", path);
-			if ((lockfd = client_get_lock(lockfile)) == -1) {
-				log_debug("didn't get lock");
+			if ((lockfd = client_get_lock(lockfile)) < 0) {
+				log_debug("didn't get lock (%d)", lockfd);
+
 				free(lockfile);
-				goto retry;
+				lockfile = NULL;
+
+				if (lockfd == -2)
+					goto retry;
 			}
-			log_debug("got lock");
+			log_debug("got lock (%d)", lockfd);
 
 			/*
 			 * Always retry at least once, even if we got the lock,
@@ -148,7 +150,7 @@ retry:
 			goto retry;
 		}
 
-		if (unlink(path) != 0 && errno != ENOENT) {
+		if (lockfd >= 0 && unlink(path) != 0 && errno != ENOENT) {
 			free(lockfile);
 			close(lockfd);
 			return (-1);
@@ -156,7 +158,7 @@ retry:
 		fd = server_start(base, lockfd, lockfile);
 	}
 
-	if (locked) {
+	if (locked && lockfd >= 0) {
 		free(lockfile);
 		close(lockfd);
 	}
diff --git a/server.c b/server.c
index d950ed77..c45e8a2c 100644
--- a/server.c
+++ b/server.c
@@ -195,9 +195,11 @@ server_start(struct event_base *base, int lockfd, char *lockfile)
 	server_update_socket();
 	server_client_create(pair[1]);
 
-	unlink(lockfile);
-	free(lockfile);
-	close(lockfd);
+	if (lockfd >= 0) {
+		unlink(lockfile);
+		free(lockfile);
+		close(lockfd);
+	}
 
 	start_cfg();
 

From 3ff46b2e43d48376f74c0fd74b5616925d4063f0 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 23:22:51 +0000
Subject: [PATCH 13/15] Shell command from -c doesn't have to be global, pass
 it as an argument.

---
 client.c | 26 ++++++++++++++------------
 tmux.c   | 11 +++++------
 tmux.h   |  3 +--
 3 files changed, 20 insertions(+), 20 deletions(-)

diff --git a/client.c b/client.c
index 8144dd1c..5987efa5 100644
--- a/client.c
+++ b/client.c
@@ -53,7 +53,7 @@ enum msgtype	 client_exittype;
 const char	*client_exitsession;
 int		 client_attached;
 
-__dead void	client_exec(const char *);
+__dead void	client_exec(const char *,const char *);
 int		client_get_lock(char *);
 int		client_connect(struct event_base *, const char *, int);
 void		client_send_identify(const char *, const char *);
@@ -62,7 +62,7 @@ void		client_write(int, const char *, size_t);
 void		client_signal(int);
 void		client_dispatch(struct imsg *, void *);
 void		client_dispatch_attached(struct imsg *);
-void		client_dispatch_wait(struct imsg *);
+void		client_dispatch_wait(struct imsg *, const char *);
 const char     *client_exit_message(void);
 
 /*
@@ -213,7 +213,8 @@ client_exit_message(void)
 
 /* Client main loop. */
 int
-client_main(struct event_base *base, int argc, char **argv, int flags)
+client_main(struct event_base *base, int argc, char **argv, int flags,
+    const char *shellcmd)
 {
 	struct cmd		*cmd;
 	struct cmd_list		*cmdlist;
@@ -234,7 +235,7 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 
 	/* Set up the initial command. */
 	cmdflags = 0;
-	if (shell_cmd != NULL) {
+	if (shellcmd != NULL) {
 		msg = MSG_SHELL;
 		cmdflags = CMD_STARTSERVER;
 	} else if (argc == 0) {
@@ -276,7 +277,8 @@ client_main(struct event_base *base, int argc, char **argv, int flags)
 		}
 		return (1);
 	}
-	client_peer = proc_add_peer(client_proc, fd, client_dispatch, NULL);
+	client_peer = proc_add_peer(client_proc, fd, client_dispatch,
+	    (void *)shellcmd);
 
 	/* Save these before pledge(). */
 	if ((cwd = getcwd(path, sizeof path)) == NULL) {
@@ -450,12 +452,12 @@ client_write(int fd, const char *data, size_t size)
 
 /* Run command in shell; used for -c. */
 __dead void
-client_exec(const char *shell)
+client_exec(const char *shell, const char *shellcmd)
 {
 	const char	*name, *ptr;
 	char		*argv0;
 
-	log_debug("shell %s, command %s", shell, shell_cmd);
+	log_debug("shell %s, command %s", shell, shellcmd);
 
 	ptr = strrchr(shell, '/');
 	if (ptr != NULL && *(ptr + 1) != '\0')
@@ -473,7 +475,7 @@ client_exec(const char *shell)
 	setblocking(STDERR_FILENO, 1);
 	closefrom(STDERR_FILENO + 1);
 
-	execl(shell, argv0, "-c", shell_cmd, (char *) NULL);
+	execl(shell, argv0, "-c", shellcmd, (char *) NULL);
 	fatal("execl failed");
 }
 
@@ -519,7 +521,7 @@ client_signal(int sig)
 
 /* Callback for client read events. */
 void
-client_dispatch(struct imsg *imsg, __unused void *arg)
+client_dispatch(struct imsg *imsg, void *arg)
 {
 	if (imsg == NULL) {
 		client_exitreason = CLIENT_EXIT_LOST_SERVER;
@@ -531,12 +533,12 @@ client_dispatch(struct imsg *imsg, __unused void *arg)
 	if (client_attached)
 		client_dispatch_attached(imsg);
 	else
-		client_dispatch_wait(imsg);
+		client_dispatch_wait(imsg, arg);
 }
 
 /* Dispatch imsgs when in wait state (before MSG_READY). */
 void
-client_dispatch_wait(struct imsg *imsg)
+client_dispatch_wait(struct imsg *imsg, const char *shellcmd)
 {
 	char			*data;
 	ssize_t			 datalen;
@@ -616,7 +618,7 @@ client_dispatch_wait(struct imsg *imsg)
 			fatalx("bad MSG_SHELL string");
 
 		clear_signals(0);
-		client_exec(data);
+		client_exec(data, shellcmd);
 		/* NOTREACHED */
 	case MSG_DETACH:
 	case MSG_DETACHKILL:
diff --git a/tmux.c b/tmux.c
index f2143755..7d49dd30 100644
--- a/tmux.c
+++ b/tmux.c
@@ -39,7 +39,6 @@ struct options	*global_s_options;	/* session options */
 struct options	*global_w_options;	/* window options */
 struct environ	*global_environ;
 
-char		*shell_cmd;
 struct timeval	 start_time;
 const char	*socket_path;
 
@@ -184,7 +183,7 @@ find_home(void)
 int
 main(int argc, char **argv)
 {
-	char		*path, *label, **var, tmp[PATH_MAX];
+	char		*path, *label, **var, tmp[PATH_MAX], *shellcmd = NULL;
 	const char	*s;
 	int		 opt, flags, keys;
 
@@ -203,8 +202,8 @@ main(int argc, char **argv)
 			flags |= CLIENT_256COLOURS;
 			break;
 		case 'c':
-			free(shell_cmd);
-			shell_cmd = xstrdup(optarg);
+			free(shellcmd);
+			shellcmd = xstrdup(optarg);
 			break;
 		case 'C':
 			if (flags & CLIENT_CONTROL)
@@ -241,7 +240,7 @@ main(int argc, char **argv)
 	argc -= optind;
 	argv += optind;
 
-	if (shell_cmd != NULL && argc != 0)
+	if (shellcmd != NULL && argc != 0)
 		usage();
 
 	if (pledge("stdio rpath wpath cpath flock fattr unix getpw sendfd "
@@ -318,5 +317,5 @@ main(int argc, char **argv)
 	free(label);
 
 	/* Pass control to the client. */
-	exit(client_main(event_init(), argc, argv, flags));
+	exit(client_main(event_init(), argc, argv, flags, shellcmd));
 }
diff --git a/tmux.h b/tmux.h
index 50d7fb03..f4638bc8 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1431,7 +1431,6 @@ extern struct options *global_options;
 extern struct options *global_s_options;
 extern struct options *global_w_options;
 extern struct environ *global_environ;
-extern char		*shell_cmd;
 extern struct timeval	 start_time;
 extern const char	*socket_path;
 const char	*getshell(void);
@@ -1732,7 +1731,7 @@ int	cmd_string_parse(const char *, struct cmd_list **, const char *,
 void	cmd_wait_for_flush(void);
 
 /* client.c */
-int	client_main(struct event_base *, int, char **, int);
+int	client_main(struct event_base *, int, char **, int, const char *);
 
 /* key-bindings.c */
 RB_PROTOTYPE(key_bindings, key_binding, entry, key_bindings_cmp);

From 62d3af17f9e6aec244ab1d91c1c46fdbbf6f8a86 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Tue, 24 Nov 2015 23:46:15 +0000
Subject: [PATCH 14/15] Make environ_set va_args and use it to tidy up some
 calls. Also add a missing word in manpage (from jmc).

---
 cmd-set-environment.c |  4 ++--
 environ.c             | 46 ++++++++++++++++++++++++++++++-------------
 server-fn.c           | 11 +++++------
 tmux.1                |  2 +-
 tmux.c                |  2 +-
 tmux.h                |  6 ++++--
 window.c              |  7 +++----
 7 files changed, 48 insertions(+), 30 deletions(-)

diff --git a/cmd-set-environment.c b/cmd-set-environment.c
index 864e1d9b..2c0010af 100644
--- a/cmd-set-environment.c
+++ b/cmd-set-environment.c
@@ -79,13 +79,13 @@ cmd_set_environment_exec(struct cmd *self, struct cmd_q *cmdq)
 			cmdq_error(cmdq, "can't specify a value with -r");
 			return (CMD_RETURN_ERROR);
 		}
-		environ_set(env, name, NULL);
+		environ_clear(env, name);
 	} else {
 		if (value == NULL) {
 			cmdq_error(cmdq, "no value specified");
 			return (CMD_RETURN_ERROR);
 		}
-		environ_set(env, name, value);
+		environ_set(env, name, "%s", value);
 	}
 
 	return (CMD_RETURN_NORMAL);
diff --git a/environ.c b/environ.c
index 43a9ce01..de560896 100644
--- a/environ.c
+++ b/environ.c
@@ -83,8 +83,12 @@ environ_copy(struct environ *srcenv, struct environ *dstenv)
 {
 	struct environ_entry	*envent;
 
-	RB_FOREACH(envent, environ, srcenv)
-		environ_set(dstenv, envent->name, envent->value);
+	RB_FOREACH(envent, environ, srcenv) {
+		if (envent->value == NULL)
+			environ_clear(dstenv, envent->name);
+		else
+			environ_set(dstenv, envent->name, "%s", envent->value);
+	}
 }
 
 /* Find an environment variable. */
@@ -99,23 +103,37 @@ environ_find(struct environ *env, const char *name)
 
 /* Set an environment variable. */
 void
-environ_set(struct environ *env, const char *name, const char *value)
+environ_set(struct environ *env, const char *name, const char *fmt, ...)
+{
+	struct environ_entry	*envent;
+	va_list			 ap;
+
+	va_start(ap, fmt);
+	if ((envent = environ_find(env, name)) != NULL) {
+		free(envent->value);
+		xvasprintf(&envent->value, fmt, ap);
+	} else {
+		envent = xmalloc(sizeof *envent);
+		envent->name = xstrdup(name);
+		xvasprintf(&envent->value, fmt, ap);
+		RB_INSERT(environ, env, envent);
+	}
+	va_end(ap);
+}
+
+/* Clear an environment variable. */
+void
+environ_clear(struct environ *env, const char *name)
 {
 	struct environ_entry	*envent;
 
 	if ((envent = environ_find(env, name)) != NULL) {
 		free(envent->value);
-		if (value != NULL)
-			envent->value = xstrdup(value);
-		else
-			envent->value = NULL;
+		envent->value = NULL;
 	} else {
 		envent = xmalloc(sizeof *envent);
 		envent->name = xstrdup(name);
-		if (value != NULL)
-			envent->value = xstrdup(value);
-		else
-			envent->value = NULL;
+		envent->value = NULL;
 		RB_INSERT(environ, env, envent);
 	}
 }
@@ -134,7 +152,7 @@ environ_put(struct environ *env, const char *var)
 	name = xstrdup(var);
 	name[strcspn(name, "=")] = '\0';
 
-	environ_set(env, name, value);
+	environ_set(env, name, "%s", value);
 	free(name);
 }
 
@@ -166,9 +184,9 @@ environ_update(const char *vars, struct environ *srcenv,
 	copyvars = next = xstrdup(vars);
 	while ((var = strsep(&next, " ")) != NULL) {
 		if ((envent = environ_find(srcenv, var)) == NULL)
-			environ_set(dstenv, var, NULL);
+			environ_clear(dstenv, var);
 		else
-			environ_set(dstenv, envent->name, envent->value);
+			environ_set(dstenv, envent->name, "%s", envent->value);
 	}
 	free(copyvars);
 }
diff --git a/server-fn.c b/server-fn.c
index 3e4b6116..a22c964d 100644
--- a/server-fn.c
+++ b/server-fn.c
@@ -34,20 +34,19 @@ void		server_callback_identify(int, short, void *);
 void
 server_fill_environ(struct session *s, struct environ *env)
 {
-	char	var[PATH_MAX], *term;
-	u_int	idx;
-	long	pid;
+	char	*term;
+	u_int	 idx;
+	long	 pid;
 
 	if (s != NULL) {
 		term = options_get_string(global_options, "default-terminal");
-		environ_set(env, "TERM", term);
+		environ_set(env, "TERM", "%s", term);
 
 		idx = s->id;
 	} else
 		idx = (u_int)-1;
 	pid = getpid();
-	xsnprintf(var, sizeof var, "%s,%ld,%u", socket_path, pid, idx);
-	environ_set(env, "TMUX", var);
+	environ_set(env, "TMUX", "%s,%ld,%u", socket_path, pid, idx);
 }
 
 void
diff --git a/tmux.1 b/tmux.1
index 8fa6ad55..454af1d2 100644
--- a/tmux.1
+++ b/tmux.1
@@ -750,7 +750,7 @@ If
 is given, all sessions but the specified one is killed.
 The
 .Fl C
-clears alerts (bell, activity, or silence) in all windows linked to the
+flag clears alerts (bell, activity, or silence) in all windows linked to the
 session.
 .It Xo Ic list-clients
 .Op Fl F Ar format
diff --git a/tmux.c b/tmux.c
index 7d49dd30..68f0092d 100644
--- a/tmux.c
+++ b/tmux.c
@@ -273,7 +273,7 @@ main(int argc, char **argv)
 	for (var = environ; *var != NULL; var++)
 		environ_put(global_environ, *var);
 	if (getcwd(tmp, sizeof tmp) != NULL)
-		environ_set(global_environ, "PWD", tmp);
+		environ_set(global_environ, "PWD", "%s", tmp);
 
 	global_options = options_create(NULL);
 	options_table_populate_tree(OPTIONS_TABLE_SERVER, global_options);
diff --git a/tmux.h b/tmux.h
index f4638bc8..2acfc75f 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1567,7 +1567,9 @@ struct environ_entry *environ_first(struct environ *);
 struct environ_entry *environ_next(struct environ_entry *);
 void	environ_copy(struct environ *, struct environ *);
 struct environ_entry *environ_find(struct environ *, const char *);
-void	environ_set(struct environ *, const char *, const char *);
+void printflike(3, 4) environ_set(struct environ *, const char *, const char *,
+	    ...);
+void	environ_clear(struct environ *, const char *);
 void	environ_put(struct environ *, const char *);
 void	environ_unset(struct environ *, const char *);
 void	environ_update(const char *, struct environ *, struct environ *);
@@ -1739,7 +1741,7 @@ RB_PROTOTYPE(key_tables, key_table, entry, key_table_cmp);
 extern struct key_tables key_tables;
 int	 key_table_cmp(struct key_table *, struct key_table *);
 int	 key_bindings_cmp(struct key_binding *, struct key_binding *);
-struct	 key_table *key_bindings_get_table(const char *, int);
+struct key_table *key_bindings_get_table(const char *, int);
 void	 key_bindings_unref_table(struct key_table *);
 void	 key_bindings_add(const char *, key_code, int, struct cmd_list *);
 void	 key_bindings_remove(const char *, key_code);
diff --git a/window.c b/window.c
index 8ee517a1..deda2895 100644
--- a/window.c
+++ b/window.c
@@ -808,7 +808,7 @@ window_pane_spawn(struct window_pane *wp, int argc, char **argv,
     struct termios *tio, char **cause)
 {
 	struct winsize	 ws;
-	char		*argv0, *cmd, **argvp, paneid[16];
+	char		*argv0, *cmd, **argvp;
 	const char	*ptr, *first, *home;
 	struct termios	 tio2;
 	int		 i;
@@ -863,9 +863,8 @@ window_pane_spawn(struct window_pane *wp, int argc, char **argv,
 		closefrom(STDERR_FILENO + 1);
 
 		if (path != NULL)
-			environ_set(env, "PATH", path);
-		xsnprintf(paneid, sizeof paneid, "%%%u", wp->id);
-		environ_set(env, "TMUX_PANE", paneid);
+			environ_set(env, "PATH", "%s", path);
+		environ_set(env, "TMUX_PANE", "%%%u", wp->id);
 		environ_push(env);
 
 		clear_signals(1);

From ac8678aefe157d7e40c5bcedd12333eaedf0df92 Mon Sep 17 00:00:00 2001
From: nicm <nicm>
Date: Wed, 25 Nov 2015 07:58:55 +0000
Subject: [PATCH 15/15] Don't print error if none to print.

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

diff --git a/client.c b/client.c
index 5987efa5..516ed3bf 100644
--- a/client.c
+++ b/client.c
@@ -373,7 +373,7 @@ client_main(struct event_base *base, int argc, char **argv, int flags,
 			printf("%%exit\n");
 		printf("\033\\");
 		tcsetattr(STDOUT_FILENO, TCSAFLUSH, &saved_tio);
-	} else
+	} else if (client_exitreason != CLIENT_EXIT_NONE)
 		fprintf(stderr, "%s\n", client_exit_message());
 	setblocking(STDIN_FILENO, 1);
 	return (client_exitval);