You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: blocking.rs
    path of file: ./repos/glommio/glommio/src/sys
    
    the code of the file until where you have to start completion: use crate::{
    executor::bind_to_cpu_set,
    sys::{InnerSource, SleepNotifier},
    PoolPlacement,
};
use ahash::AHashMap;
use alloc::rc::Rc;
use core::fmt::{Debug, Formatter};
use flume::{Receiver, Sender};
use std::{
    cell::{Cell, RefCell},
    convert::{TryFrom, TryInto},
    ffi::CString,
    future::Future,
    io,
    os::unix::{ffi::OsStrExt, prelude::*},
    path::{Path, PathBuf},
    pin::Pin,
    sync::Arc,
    thread::JoinHandle,
};

// So hard to copy/clone io::Err
    
    pub(super) fn flush(&self) -> usize {
        let mut woke = 0;
        let mut waiters = self.sources.borrow_mut();
        for x in self.rx.try_iter() {
            let id = x.id;
            let res = x.res;

            let src = waiters.remove(&id).unwrap();
            let mut inner_source = src.borrow_mut();
            inner_source.wakers.result.replace(
                res.try_into()
                    .expect("not a valid blocking operation's result"),
            );
            inner_source.wakers.wake_waiters();

            woke += 1;
        }
        woke
    }