import asyncio, io, os, sys

class BufferedReaderWithProbe(io.BufferedReader):
    def close(self):
        # Probe before status
        fd = self.fileno()
        print(f"closing {self} (fd {fd})")
        try:
            os.fstat(fd); fd_state = "still OPEN"
        except OSError as e:
            fd_state = f"already closed ({e.strerror})"
        # Open a new pipe to see what fds we get
        # Kernel should reuse lowest free number
        newfd_reader, newfd_writer = os.pipe()
        print(f"  is fd {fd} already closed? {fd_state}")
        print(f"  fresh os.pipe() got fds {newfd_reader},{newfd_writer}")

        # Do normal BufferedReader close
        try:
            print("calling BufferedReader.close")
            super().close()
        finally:

            # Probe after status
            print("Status after close:")
            for fd in (newfd_reader, newfd_writer):
                try:
                    os.fstat(fd); print(f"  fresh fd {fd}: alive")
                except OSError as e:
                    print(f"  fresh fd {fd}: DEAD ({e.strerror})  <-- stolen")

async def main():
    loop = asyncio.get_running_loop()
    pipe_read_fd, pipe_write_fd = os.pipe()
    probe_reader = BufferedReaderWithProbe(io.FileIO(pipe_read_fd, "rb"))
    transport, _ = await loop.connect_read_pipe(asyncio.Protocol, probe_reader)
    print(f"transport {type(transport).__name__} on fd {pipe_read_fd}")
    transport.close()

if __name__ == "__main__":
    if sys.argv[1:] == ["uvloop"]:
        import uvloop; uvloop.install(); print(f"== uvloop {uvloop.__version__}")
    else:
        print(f"== stdlib asyncio {sys.version.split()[0]}")
    asyncio.run(main())

$ python repro.py
== stdlib asyncio 3.10.16
transport _UnixReadPipeTransport on fd 6
closing <BufferedReaderWithProbe name=6> (fd 6)
  is fd 6 already closed? still OPEN
  fresh os.pipe() got fds 8,9
calling BufferedReader.close
Status after close:
  fresh fd 8: alive
  fresh fd 9: alive
$ python repro.py uvloop
== uvloop 0.22.1
transport ReadUnixTransport on fd 13
closing <BufferedReaderWithProbe name=13> (fd 13)
  is fd 13 already closed? already closed (Bad file descriptor)
  fresh os.pipe() got fds 13,16
calling BufferedReader.close
Status after close:
  fresh fd 13: DEAD (Bad file descriptor)  <-- stolen
  fresh fd 16: alive