diff --git a/Python/fileutils.c b/Python/fileutils.c
index 22e72bd..2c86828 100644
--- a/Python/fileutils.c
+++ b/Python/fileutils.c
@@ -1274,7 +1274,12 @@
 #endif
 
     if (gil_held) {
-        if (PySys_Audit("open", "sOi", pathname, Py_None, flags) < 0) {
+        PyObject *pathname_obj = PyUnicode_DecodeFSDefault(pathname);
+        if (pathname_obj == NULL) {
+            return -1;
+        }
+        if (PySys_Audit("open", "OOi", pathname_obj, Py_None, flags) < 0) {
+            Py_DECREF(pathname_obj);
             return -1;
         }
 
@@ -1284,12 +1289,16 @@
             Py_END_ALLOW_THREADS
         } while (fd < 0
                  && errno == EINTR && !(async_err = PyErr_CheckSignals()));
-        if (async_err)
-            return -1;
-        if (fd < 0) {
-            PyErr_SetFromErrnoWithFilename(PyExc_OSError, pathname);
+        if (async_err) {
+            Py_DECREF(pathname_obj);
             return -1;
         }
+        if (fd < 0) {
+            PyErr_SetFromErrnoWithFilenameObjects(PyExc_OSError, pathname_obj, NULL);
+            Py_DECREF(pathname_obj);
+            return -1;
+        }
+        Py_DECREF(pathname_obj);
     }
     else {
         fd = open(pathname, flags);
@@ -1385,9 +1394,15 @@
 FILE*
 _Py_fopen(const char *pathname, const char *mode)
 {
-    if (PySys_Audit("open", "ssi", pathname, mode, 0) < 0) {
+    PyObject *pathname_obj = PyUnicode_DecodeFSDefault(pathname);
+    if (pathname_obj == NULL) {
         return NULL;
     }
+    if (PySys_Audit("open", "Osi", pathname_obj, mode, 0) < 0) {
+        Py_DECREF(pathname_obj);
+        return NULL;
+    }
+    Py_DECREF(pathname_obj);
 
     FILE *f = fopen(pathname, mode);
     if (f == NULL)