Feature request: Ability to return a value from aco_yield() about libaco

[hnes]

Hi Mahdi @mrakh, sorry for the late response. I'm very glad this library is useful to you.

I prefer the usage described below to solve your problem.

// `MyArg` is the struct the co arg is pointing to
struct MyArg{
    // yieldReason: [sleep, poll_fd, poll_iouring]
    int yieldReason;
    void* yieldRetValue
    // other members
    /* ... */
}

// Inside coroutine
/*   setup MyArg to this co */
/*   prepare io_uring_task */
/*   bind this co to the io_uring_task */
/*   submit io_uring_task */
/*   MyArg->yieldReason = POLL_IOURING */
aco_yield()
if check MyArg->yieldRetValue ok 
   handle the ready io_uring_task
else
   handle the error

// inside the scheduler
for{
    // scheduler loop
    // do other stuff...
    // io_uring stuff
    io_uring_peek_cqe // nonblock waiting
    if co ready
        // resume the ready co
        aco_resume(co)
    end
    // do other stuff...
}

I think it is better to let the scheduler do the as minimal task as possible, including event polling like fd polling, and io_uring task polling in this case. (I didn't yet dive very deeply into the io_uring, so please correct me if I got a mistake.)