From 70ddb405197f3db76db4a1e4a5ad5b9d8bb6ec09 Mon Sep 17 00:00:00 2001
From: Yakun Xu <xyk@google.com>
Date: Thu, 27 Aug 2020 14:02:37 +0800
Subject: [PATCH] [diag] clear output in case no output given (#5465)

The stop command doesn't write anything to the output buffer.
---
 src/core/diags/factory_diags.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/core/diags/factory_diags.cpp b/src/core/diags/factory_diags.cpp
index fc41cc92d..482fe2e8a 100644
--- a/src/core/diags/factory_diags.cpp
+++ b/src/core/diags/factory_diags.cpp
@@ -535,7 +535,7 @@ exit:
     switch (error)
     {
     case OT_ERROR_NONE:
-
+        aOutput[0] = '\0'; // In case there is no output.
         IgnoreError(ProcessCmd(argCount, &aArgsector[0], aOutput, aOutputMaxLen));
         break;