diff --git a/src/modules/_Stdio/file.c b/src/modules/_Stdio/file.c
index 43df9cf22357d9677af1e401d57960e21d0d9b96..5e7ffeb78bc39e0a68bcfb9f8b37f0f27b9e56cd 100644
--- a/src/modules/_Stdio/file.c
+++ b/src/modules/_Stdio/file.c
@@ -3894,6 +3894,8 @@ static void file_errno(INT32 args)
  *!     @[FILE_EXCLUSIVE]
  *!   @value 0x0400
  *!     @[FILE_NONBLOCKING]
+ *!   @value 0x0080
+ *!     @[PROP_TTY]
  *!   @value 0x0040
  *!     @[PROP_SEND_FD]
  *!   @value 0x0010
@@ -5965,6 +5967,11 @@ static void f_get_all_active_fd(INT32 args)
  *!
  *!   The @[Stdio.File] object supports tty operations.
  *!
+ *! @note
+ *!   This constant is only present on platforms where pseudo tty
+ *!   (aka pty) operations are available, and may thus be used to
+ *!   detect whether such operations should be attempted.
+ *!
  *! @seealso
  *!   @[Stdio.File()->pipe()]
  */