diff --git a/kitty/child-monitor.c b/kitty/child-monitor.c
index 1edab9445..3e3a0e1f5 100644
--- a/kitty/child-monitor.c
+++ b/kitty/child-monitor.c
@@ -1548,7 +1548,7 @@ static PyMethodDef module_methods[] = {
     {"add_timer", (PyCFunction)add_python_timer, METH_VARARGS, ""},
     {"remove_timer", (PyCFunction)remove_python_timer, METH_VARARGS, ""},
     METHODB(monitor_pid, METH_VARARGS),
-    {"set_iutf8", (PyCFunction)pyset_iutf8, METH_VARARGS, ""},
+    {"set_iutf8_winid", (PyCFunction)pyset_iutf8, METH_VARARGS, ""},
     {NULL}  /* Sentinel */
 };
 
diff --git a/kitty/child.py b/kitty/child.py
index 137c8408d..cc9b48afd 100644
--- a/kitty/child.py
+++ b/kitty/child.py
@@ -180,7 +180,7 @@ class Child:
         self.forked = True
         master, slave = os.openpty()  # Note that master and slave are in blocking mode
         remove_cloexec(slave)
-        fast_data_types.set_iutf8(master, True)
+        fast_data_types.set_iutf8_fd(master, True)
         stdin, self.stdin = self.stdin, None
         ready_read_fd, ready_write_fd = os.pipe()
         remove_cloexec(ready_read_fd)
diff --git a/kitty/data-types.c b/kitty/data-types.c
index 91b22a8da..26f7d7041 100644
--- a/kitty/data-types.c
+++ b/kitty/data-types.c
@@ -192,7 +192,7 @@ static PyMethodDef module_methods[] = {
     {"normal_tty", normal_tty, METH_VARARGS, ""},
     {"raw_tty", raw_tty, METH_VARARGS, ""},
     {"close_tty", close_tty, METH_VARARGS, ""},
-    {"set_iutf8", (PyCFunction)pyset_iutf8, METH_VARARGS, ""},
+    {"set_iutf8_fd", (PyCFunction)pyset_iutf8, METH_VARARGS, ""},
     {"thread_write", (PyCFunction)cm_thread_write, METH_VARARGS, ""},
     {"parse_bytes", (PyCFunction)parse_bytes, METH_VARARGS, ""},
     {"parse_bytes_dump", (PyCFunction)parse_bytes_dump, METH_VARARGS, ""},
diff --git a/kitty/window.py b/kitty/window.py
index 4ad4f3d57..643c90155 100644
--- a/kitty/window.py
+++ b/kitty/window.py
@@ -279,7 +279,7 @@ class Window:
 
     # screen callbacks {{{
     def use_utf8(self, on):
-        get_boss().child_monitor.set_iutf8(self.id, on)
+        get_boss().child_monitor.set_iutf8_winid(self.id, on)
 
     def focus_changed(self, focused):
         if focused: