Initialise log_fd to -1, prevents spurious disconnection of the client when it

ends up as fd 0 (likely if the server is started with "tmux start").

Also add some extra debugging messages to server.c.

server.c

@@ -110,6 +110,7 @@ server_create_client(int fd)
 		}
 	}
 	ARRAY_ADD(&clients, c);
+	log_debug("new client %d", fd);
 }
 
 /* Find client index. */
@@ -257,6 +258,7 @@ server_main(int srv_fd)
 	time_t		 now, last;
 
 	siginit();
+	log_debug("server socket is %d", srv_fd);
 
 	last = time(NULL);
 
@@ -901,6 +903,7 @@ server_lost_client(struct client *c)
 		if (ARRAY_ITEM(&clients, i) == c)
 			ARRAY_SET(&clients, i, NULL);
 	}
+	log_debug("lost client %d", c->ibuf.fd);
 
 	tty_free(&c->tty);
 

tty.c

@@ -49,6 +49,7 @@ tty_init(struct tty *tty, int fd, char *path, char *term)
 {
 	tty->path = xstrdup(path);
 	tty->fd = fd;
+	tty->log_fd = -1;
 
 	if (term == NULL || *term == '\0')
 		tty->termname = xstrdup("unknown");