from typing import Callable, Iterable

_Reader = Callable[[int], bytes]

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: ...