98fae82da42d038b9ed0c87b557524fd03345191 tmux support
diff --git a/config.def.h b/config.def.h
index b41747f..ed4a329 100644
--- a/config.def.h
+++ b/config.def.h
@@ -20,6 +20,14 @@ static char shell[] = "/bin/sh";
 static char *utmp = NULL;
 static char stty_args[] = "stty raw pass8 nl -echo -iexten -cstopb 38400";

+/* Multiplexer wrapper */
+static int use_mux = 0;
+static char *mux_new[] = {"/usr/bin/tmux", "new-session", "-s", NULL, "--"};
+static char mux_post[] =
+	"tmux list-clients -t \"$MUX_NM\" 2>/dev/null"
+	"| { read -r _ && ! read -r _; }"
+	"&& tmux kill-session -t \"$MUX_NM\"";
+
 /* identification sequence returned in DA and DECID */
 static char vtiden[] = "\033[?6c";

diff --git a/st.c b/st.c
index 2594c65..d41b805 100644
--- a/st.c
+++ b/st.c
@@ -560,6 +560,9 @@ typedef struct {
 static Fontcache frc[16];
 static int frclen = 0;

+/* Multiplexer session name */
+static char mux_nm[64] = {0};
+
 ssize_t
 xwrite(int fd, const char *s, size_t len)
 {
@@ -1366,6 +1369,16 @@ execsh(void)
 	signal(SIGTERM, SIG_DFL);
 	signal(SIGALRM, SIG_DFL);

+	if (use_mux) {
+		int i = sizeof(mux_new)/sizeof(mux_new[0]), j = 0;
+		while(args[j++]);
+		char *margs[i + j];
+		while(j--) { margs[i + j] = args[j]; }
+		while(i--) { margs[i] = mux_new[i] ? mux_new[i] : mux_nm; }
+		execvp(mux_new[0], margs);
+		_exit(1);
+	}
+
 	execvp(prog, args);
 	_exit(1);
 }
@@ -4177,6 +4190,11 @@ cmessage(XEvent *e)
 			xw.state &= ~WIN_FOCUSED;
 		}
 	} else if (e->xclient.data.l[0] == xw.wmdeletewin) {
+		if (use_mux) {
+			setenv("MUX_NM", mux_nm, 1);
+			if (system(mux_post) != 0)
+				fprintf(stderr, "mux_post execution error\n");
+		}
 		/* Send SIGHUP to shell */
 		kill(pid, SIGHUP);
 		exit(0);
@@ -4325,7 +4343,7 @@ usage(void)
 	die("usage: %s [-aiv] [-c class] [-f font] [-g geometry]"
 	    " [-n name] [-o file]\n"
 	    "          [-T title] [-t title] [-w windowid]"
-	    " [[-e] command [args ...]]\n"
+	    " [-m|-M] [[-e] command [args ...]]\n"
 	    "       %s [-aiv] [-c class] [-f font] [-g geometry]"
 	    " [-n name] [-o file]\n"
 	    "          [-T title] [-t title] [-w windowid] -l line"
@@ -4368,6 +4386,12 @@ main(int argc, char *argv[])
 	case 'l':
 		opt_line = EARGF(usage());
 		break;
+	case 'm':
+		use_mux = 1;
+		break;
+	case 'M':
+		use_mux = 0;
+		break;
 	case 'n':
 		opt_name = EARGF(usage());
 		break;
@@ -4392,6 +4416,9 @@ run:
 		if (!opt_title && !opt_line)
 			opt_title = basename(xstrdup(argv[0]));
 	}
+	if (use_mux) {
+		snprintf(mux_nm, sizeof(mux_nm), "%.43s-%d", (opt_name ? opt_name : "st"), getpid());
+	}
 	setlocale(LC_CTYPE, "");
 	XSetLocaleModifiers("");
 	tnew(MAX(cols, 1), MAX(rows, 1));