if fd.pd.runtimeCtx == 0 {
		return ErrNoDeadline
	}
	runtime_pollSetDeadline(fd.pd.runtimeCtx, d, mode)
	return nil
}

// IsPollDescriptor reports whether fd is the descriptor being used by the poller.
// This is only used for testing.
//
// IsPollDescriptor should be an internal detail,
// but widely used packages access it using linkname.
// Notable members of the hall of shame include:

}

func isInterrupted(err error) bool {
	return err != nil && stringslite.HasSuffix(err.Error(), "interrupted")
}

// IsPollDescriptor reports whether fd is the descriptor being used by the poller.
// This is only used for testing.
func IsPollDescriptor(fd uintptr) bool {
	return false
}

// RawControl invokes the user-defined function f for a non-IO
// operation.

	os.Setenv("GODEBUG", godebug)

	if os.Getenv("GO_EXEC_TEST_PID") != "" {
		return
	}
	if runtime.GOOS == "windows" {
		return
	}
	for fd := uintptr(3); fd <= 100; fd++ {
		if poll.IsPollDescriptor(fd) {
			continue
		}

		if fdtest.Exists(fd) {
			haveUnexpectedFDs = true
			return
		}
	}
}

// TestMain allows the test binary to impersonate many other binaries,