1 files changed, 6 insertions, 50 deletions

diff --git a/Modules/_io/textio.c b/Modules/_io/textio.c
index 6ba7393..f45a697 100644
--- a/Modules/_io/textio.c
+++ b/Modules/_io/textio.c
@@ -1060,7 +1060,6 @@ _io_TextIOWrapper___init___impl(textio *self, PyObject *buffer,
     PyObject *raw, *codec_info = NULL;
     PyObject *res;
     int r;
-    int use_locale_encoding = 0; // Use locale encoding even in UTF-8 mode.
 
     self->ok = 0;
     self->detached = 0;
@@ -1074,10 +1073,6 @@ _io_TextIOWrapper___init___impl(textio *self, PyObject *buffer,
             }
         }
     }
-    else if (strcmp(encoding, "locale") == 0) {
-        encoding = NULL;
-        use_locale_encoding = 1;
-    }
 
     if (errors == Py_None) {
         errors = &_Py_ID(strict);
@@ -1114,57 +1109,18 @@ _io_TextIOWrapper___init___impl(textio *self, PyObject *buffer,
     self->encodefunc = NULL;
     self->b2cratio = 0.0;
 
-#ifdef MS_WINDOWS
-    // os.device_encoding() on Unix is the locale encoding or UTF-8
-    // according to UTF-8 Mode.
-    // Since UTF-8 mode shouldn't affect `encoding="locale"`, we call
-    // os.device_encoding() only on Windows.
-    if (encoding == NULL) {
-        /* Try os.device_encoding(fileno) */
-        PyObject *fileno;
-        _PyIO_State *state = IO_STATE();
-        if (state == NULL)
-            goto error;
-        fileno = PyObject_CallMethodNoArgs(buffer, &_Py_ID(fileno));
-        /* Ignore only AttributeError and UnsupportedOperation */
-        if (fileno == NULL) {
-            if (PyErr_ExceptionMatches(PyExc_AttributeError) ||
-                PyErr_ExceptionMatches(state->unsupported_operation)) {
-                PyErr_Clear();
-            }
-            else {
-                goto error;
-            }
-        }
-        else {
-            int fd = _PyLong_AsInt(fileno);
-            Py_DECREF(fileno);
-            if (fd == -1 && PyErr_Occurred()) {
-                goto error;
-            }
-
-            self->encoding = _Py_device_encoding(fd);
-            if (self->encoding == NULL)
-                goto error;
-            else if (!PyUnicode_Check(self->encoding))
-                Py_CLEAR(self->encoding);
-        }
+    if (encoding == NULL && _PyRuntime.preconfig.utf8_mode) {
+        _Py_DECLARE_STR(utf_8, "utf-8");
+        self->encoding = Py_NewRef(&_Py_STR(utf_8));
     }
-#endif
-
-    if (encoding == NULL && self->encoding == NULL) {
-        if (_PyRuntime.preconfig.utf8_mode && !use_locale_encoding) {
-            _Py_DECLARE_STR(utf_8, "utf-8");
-            self->encoding = Py_NewRef(&_Py_STR(utf_8));
-        }
-        else {
-            self->encoding = _Py_GetLocaleEncodingObject();
-        }
+    else if (encoding == NULL || (strcmp(encoding, "locale") == 0)) {
+        self->encoding = _Py_GetLocaleEncodingObject();
         if (self->encoding == NULL) {
             goto error;
         }
         assert(PyUnicode_Check(self->encoding));
     }
+
     if (self->encoding != NULL) {
         encoding = PyUnicode_AsUTF8(self->encoding);
         if (encoding == NULL)