From 047ce8c452087809f5ab10d7a2ea58c8709a8da3 Mon Sep 17 00:00:00 2001
From: Henry Schreiner <henry.fredrick.schreiner@cern.ch>
Date: Tue, 11 Jun 2019 16:17:50 -0400
Subject: [PATCH] Fix iostream when used with nogil (#1368)

---
 include/pybind11/iostream.h | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/include/pybind11/iostream.h b/include/pybind11/iostream.h
index 9119270e..72baef8f 100644
--- a/include/pybind11/iostream.h
+++ b/include/pybind11/iostream.h
@@ -43,8 +43,11 @@ private:
             // This subtraction cannot be negative, so dropping the sign
             str line(pbase(), static_cast<size_t>(pptr() - pbase()));
 
-            pywrite(line);
-            pyflush();
+            {
+                gil_scoped_acquire tmp;
+                pywrite(line);
+                pyflush();
+            }
 
             setp(pbase(), epptr());
         }