From 6fa74b7674154733d0934e2deee0860743b9ee5d Mon Sep 17 00:00:00 2001
From: Jiacheng Guo <guoamtcmp@gmail.com>
Date: Thu, 22 Apr 2021 13:16:04 +0800
Subject: [PATCH] [cli] fix false alarm when printing empty line (#6499)

The OpenThread cli may print false alarms when calling
`OutputLine("")`. Fix accordingly.
---
 examples/apps/cli/cli_uart.cpp | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/examples/apps/cli/cli_uart.cpp b/examples/apps/cli/cli_uart.cpp
index 0f3e54197..b2d271dcc 100644
--- a/examples/apps/cli/cli_uart.cpp
+++ b/examples/apps/cli/cli_uart.cpp
@@ -332,7 +332,7 @@ static int CliUartOutput(void *aContext, const char *aFormat, va_list aArguments
     if (sTxLength == 0)
     {
         rval = vsnprintf(sTxBuffer, kTxBufferSize, aFormat, aArguments);
-        VerifyOrExit(rval > 0 && rval < kTxBufferSize, otLogWarnPlat("Failed to format CLI output `%s`", aFormat));
+        VerifyOrExit(rval >= 0 && rval < kTxBufferSize, otLogWarnPlat("Failed to format CLI output `%s`", aFormat));
         sTxHead     = 0;
         sTxLength   = static_cast<uint16_t>(rval);
         sSendLength = 0;