wait_readable_win_hang.py

import anyio
import socket


async def demo():
    s1, s2 = socket.socketpair()
    with s1, s2:
        s1.setblocking(False)
        s2.setblocking(False)
        async with anyio.create_task_group() as tg:
            tg.start_soon(anyio.wait_readable, s2)
            await anyio.wait_all_tasks_blocked()
            await anyio.sleep(0.1)
            tg.cancel_scope.cancel()

    s1, s2 = socket.socketpair()
    with s1, s2:
        s1.setblocking(False)
        s2.setblocking(False)
        s1.send(b"\x00")
        await anyio.wait_readable(s2)
        print("done")

anyio.run(demo)