diff --git a/stdlib/pty.pyi b/stdlib/pty.pyi
index f943cebdb..8809b6532 100644
--- a/stdlib/pty.pyi
+++ b/stdlib/pty.pyi
@@ -1,15 +1,16 @@
+import sys
 from typing import Callable, Iterable
 
-_Reader = Callable[[int], bytes]
+if sys.platform != "win32":
+    _Reader = Callable[[int], bytes]
 
-STDIN_FILENO: int
-STDOUT_FILENO: int
-STDERR_FILENO: int
+    STDIN_FILENO: int
+    STDOUT_FILENO: int
+    STDERR_FILENO: int
 
-CHILD: int
-
-def openpty() -> tuple[int, int]: ...
-def master_open() -> tuple[int, str]: ...
-def slave_open(tty_name: str) -> int: ...
-def fork() -> tuple[int, int]: ...
-def spawn(argv: str | Iterable[str], master_read: _Reader = ..., stdin_read: _Reader = ...) -> int: ...
+    CHILD: int
+    def openpty() -> tuple[int, int]: ...
+    def master_open() -> tuple[int, str]: ...
+    def slave_open(tty_name: str) -> int: ...
+    def fork() -> tuple[int, int]: ...
+    def spawn(argv: str | Iterable[str], master_read: _Reader = ..., stdin_read: _Reader = ...) -> int: ...