diff --git a/kitty/data-types.c b/kitty/data-types.c
index 92bad6761..eca5a315b 100644
--- a/kitty/data-types.c
+++ b/kitty/data-types.c
@@ -126,6 +126,7 @@ open_tty(PyObject *self UNUSED, PyObject *args) {
     if (!read_with_timeout) flags |= O_NONBLOCK;
     static char ctty[L_ctermid+1];
     int fd = open(ctermid(ctty), flags);
+    if (fd == -1) { PyErr_SetFromErrno(PyExc_OSError); return NULL; }
     struct termios *termios_p = calloc(1, sizeof(struct termios));
     if (!termios_p) return PyErr_NoMemory();
     if (tcgetattr(fd, termios_p) != 0) { free(termios_p); PyErr_SetFromErrno(PyExc_OSError); return NULL; }