diff --git a/src/backend/modern.lisp b/src/backend/modern.lisp
index 37ad334..e63e360 100644
--- a/src/backend/modern.lisp
+++ b/src/backend/modern.lisp
@@ -176,7 +176,7 @@ as a fallback when a keyword is not in *named-colors*.")
       ;; Direct ioctl on /dev/tty — opens the real controlling terminal,
       ;; bypassing any fd weirdness from SBCL's subprocess or stream setup.
       (ignore-errors
-        (let ((tty-fd (sb-unix:unix-open "/dev/tty" sb-unix:o-rdwr 0)))
+        (let ((tty-fd (sb-unix:unix-open "/dev/tty" 2 0)))  ; O_RDWR = 2
           (when tty-fd
             (unwind-protect
                  (let* ((winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))
diff --git a/src/backend/simple.lisp b/src/backend/simple.lisp
index ab8c501..98f3e13 100644
--- a/src/backend/simple.lisp
+++ b/src/backend/simple.lisp
@@ -36,7 +36,7 @@
             (sb-alien:free-alien winsize))))
       ;; Direct ioctl on /dev/tty — opens the real controlling terminal.
       (ignore-errors
-        (let ((tty-fd (sb-unix:unix-open "/dev/tty" sb-unix:o-rdwr 0)))
+        (let ((tty-fd (sb-unix:unix-open "/dev/tty" 2 0)))  ; O_RDWR = 2
           (when tty-fd
             (unwind-protect
                  (let* ((winsize (sb-alien:make-alien sb-alien:unsigned-short 4)))