python · miss-islington · Jun 13, 2019 · Jun 12, 2019
diff --git a/Misc/NEWS.d/next/Windows/2019-06-11-15-41-34.bpo-36779.0TMw6f.rst b/Misc/NEWS.d/next/Windows/2019-06-11-15-41-34.bpo-36779.0TMw6f.rst
@@ -0,0 +1,2 @@
+Ensure ``time.tzname`` is correct on Windows when the active code page is
+set to CP_UTF7 or CP_UTF8.
diff --git a/Modules/timemodule.c b/Modules/timemodule.c
@@ -1571,6 +1571,19 @@ init_timezone(PyObject *m)
    PyModule_AddIntConstant(m, "altzone", _Py_timezone-3600);
 #endif
    PyModule_AddIntConstant(m, "daylight", _Py_daylight);
+#ifdef MS_WINDOWS
+    TIME_ZONE_INFORMATION tzinfo = {0};
+    GetTimeZoneInformation(&tzinfo);
+    otz0 = PyUnicode_FromWideChar(tzinfo.StandardName, -1);
+    if (otz0 == NULL) {
+        return -1;
+    }
+    otz1 = PyUnicode_FromWideChar(tzinfo.DaylightName, -1);
+    if (otz1 == NULL) {
+        Py_DECREF(otz0);
+        return -1;
+    }
+#else
    otz0 = PyUnicode_DecodeLocale(_Py_tzname[0], "surrogateescape");
    if (otz0 == NULL) {
        return -1;
@@ -1580,6 +1593,7 @@ init_timezone(PyObject *m)
        Py_DECREF(otz0);
        return -1;
    }
+#endif // MS_WINDOWS
    PyObject *tzname_obj = Py_BuildValue("(NN)", otz0, otz1);
    if (tzname_obj == NULL) {
        return -1;
Original file line number	Diff line number	Diff line change
		@@ -0,0 +1,2 @@
		Ensure ``time.tzname`` is correct on Windows when the active code page is
		set to CP_UTF7 or CP_UTF8.