Python3 Migrate

venv/lib/python3.7/site-packages/tornado/platform/windows.py

@@ -0,0 +1,22 @@
+# NOTE: win32 support is currently experimental, and not recommended
+# for production use.
+
+import ctypes
+import ctypes.wintypes
+
+# See: http://msdn.microsoft.com/en-us/library/ms724935(VS.85).aspx
+SetHandleInformation = ctypes.windll.kernel32.SetHandleInformation  # type: ignore
+SetHandleInformation.argtypes = (
+    ctypes.wintypes.HANDLE,
+    ctypes.wintypes.DWORD,
+    ctypes.wintypes.DWORD,
+)
+SetHandleInformation.restype = ctypes.wintypes.BOOL
+
+HANDLE_FLAG_INHERIT = 0x00000001
+
+
+def set_close_exec(fd: int) -> None:
+    success = SetHandleInformation(fd, HANDLE_FLAG_INHERIT, 0)
+    if not success:
+        raise ctypes.WinError()  # type: ignore