From e976df232941aae838b8c3dcf4b9f79f79bea705 Mon Sep 17 00:00:00 2001
From: ddzama <ddzama@opencascade.com>
Date: Mon, 4 Apr 2022 07:29:42 +0300
Subject: [PATCH] 0032920: Coding - fix checking of std::stringstream buffer
 size on VS2019/C++20

Use tellp() instead of in_avail() for testing non-empty std::stringstream state.
---
 src/Message/Message_Messenger.hxx | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/Message/Message_Messenger.hxx b/src/Message/Message_Messenger.hxx
index a804a6c527..3ee2ea3d3a 100644
--- a/src/Message/Message_Messenger.hxx
+++ b/src/Message/Message_Messenger.hxx
@@ -72,7 +72,7 @@ public:
     void Flush(Standard_Boolean doForce = Standard_False)
     {
       myStream.flush();
-      if (doForce || myStream.rdbuf()->in_avail() > 0)
+      if (doForce || myStream.tellp() != std::streampos(0))
       {
         if (myMessenger)
         {