From c5ad47ee7c7595c1d0dcf2a226742fd19d548605 Mon Sep 17 00:00:00 2001
From: Nicholas Marriott <nicholas.marriott@gmail.com>
Date: Wed, 13 Mar 2013 07:31:36 +0000
Subject: [PATCH] Only send end guard if begin was sent, from George Nachman.

---
 cmd-queue.c | 21 ++++++++++++---------
 tmux.h      |  2 +-
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/cmd-queue.c b/cmd-queue.c
index 17992a37..6ea6f468 100644
--- a/cmd-queue.c
+++ b/cmd-queue.c
@@ -152,19 +152,20 @@ cmdq_error(struct cmd_q *cmdq, const char *fmt, ...)
 }
 
 /* Print a guard line. */
-void
+int
 cmdq_guard(struct cmd_q *cmdq, const char *guard)
 {
 	struct client	*c = cmdq->client;
 
 	if (c == NULL || c->session == NULL)
-		return;
+		return 0;
 	if (!(c->flags & CLIENT_CONTROL))
-		return;
+		return 0;
 
 	evbuffer_add_printf(c->stdout_data, "%%%s %ld %u\n", guard,
 	    (long) cmdq->time, cmdq->number);
 	server_push_stdout(c);
+	return 1;
 }
 
 /* Add command list to queue and begin processing if needed. */
@@ -197,7 +198,7 @@ cmdq_continue(struct cmd_q *cmdq)
 {
 	struct cmd_q_item	*next;
 	enum cmd_retval		 retval;
-	int			 empty;
+	int			 empty, guard;
 	char			 s[1024];
 
 	notify_disable();
@@ -223,12 +224,14 @@ cmdq_continue(struct cmd_q *cmdq)
 			cmdq->time = time(NULL);
 			cmdq->number++;
 
-			cmdq_guard(cmdq, "begin");
+			guard = cmdq_guard(cmdq, "begin");
 			retval = cmdq->cmd->entry->exec(cmdq->cmd, cmdq);
-			if (retval == CMD_RETURN_ERROR)
-				cmdq_guard(cmdq, "error");
-			else
-				cmdq_guard(cmdq, "end");
+			if (guard) {
+				if (retval == CMD_RETURN_ERROR)
+				    cmdq_guard(cmdq, "error");
+				else
+				    cmdq_guard(cmdq, "end");
+			}
 
 			if (retval == CMD_RETURN_ERROR)
 				break;
diff --git a/tmux.h b/tmux.h
index 89860cb8..7c4c55be 100644
--- a/tmux.h
+++ b/tmux.h
@@ -1856,7 +1856,7 @@ int		 cmdq_free(struct cmd_q *);
 void printflike2 cmdq_print(struct cmd_q *, const char *, ...);
 void printflike2 cmdq_info(struct cmd_q *, const char *, ...);
 void printflike2 cmdq_error(struct cmd_q *, const char *, ...);
-void		 cmdq_guard(struct cmd_q *, const char *);
+int		 cmdq_guard(struct cmd_q *, const char *);
 void		 cmdq_run(struct cmd_q *, struct cmd_list *);
 void		 cmdq_append(struct cmd_q *, struct cmd_list *);
 int		 cmdq_continue(struct cmd_q *);