Issue #3187: Add sys.setfilesystemencoding.
diff --git a/Include/fileobject.h b/Include/fileobject.h
index 00ec9be..1570890 100644
--- a/Include/fileobject.h
+++ b/Include/fileobject.h
@@ -20,7 +20,8 @@
If non-NULL, this is different than the default encoding for strings
*/
PyAPI_DATA(const char *) Py_FileSystemDefaultEncoding;
-PyAPI_DATA(const int) Py_HasFileSystemDefaultEncoding;
+PyAPI_DATA(int) Py_HasFileSystemDefaultEncoding;
+PyAPI_FUNC(int) _Py_SetFileSystemEncoding(PyObject *);
/* Internal API