#6077: on Windows, fix truncation of a tempfile.TemporaryFile opened in "wt+" mode:
files opened with os.open() stop on the first \x1a (Ctrl-Z) unless os.O_BINARY is used.

Will backport to 3.1
diff --git a/Misc/NEWS b/Misc/NEWS
index 96fbbce..d3da7b9 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -12,6 +12,9 @@
 Core and Builtins
 -----------------
 
+- Issue #6077: On Windows, files opened with tempfile.TemporaryFile in "wt+"
+  mode would appear truncated on the first '0x1a' byte (aka. Ctrl+Z).
+
 - Issue #7085: Fix crash when importing some extensions in a thread
   on MacOSX 10.6.