How to sync libuv code?

Question

C++ / C#

There is just an example (below). The problem is that I need to wait for the completion of the code in after inside the process , how can I implement this correctly? Not while-loop in the end-same-ends to do?

uv_work_t *baton;

void work(uv_work_t* task) {}

void after(uv_work_t* task, int status) {
    printf("after\n");
    delete task;
}

int process()
{
    baton = new uv_work_t();
    uv_queue_work(uv_default_loop(), baton, work, after);
    printf("before\n");
    return 0;
}

PS The process itself is executed in a separate thread via pthread.

Answer 1

Start a semaphore (uv_sem_*) that wait in process and cock it in after. Something like that:

static uv_sem_t sem;
uv_work_t *baton;

void work(uv_work_t* task) {}

void after(uv_work_t* task, int status) {
    printf("after\n");
    delete task;
    uv_sem_post(&sem);
}
int process()
{
    baton = new uv_work_t();
    if (uv_sem_init(&sem, 0) < 0) {
        perror("uv_sem_init");
        return -1;
    }
    uv_queue_work(uv_default_loop(), baton, work, after);
    printf("before\n");
    uv_sem_wait(&sem);
    uv_sem_destroy(&sem);
    return 0;
}

But the question arises: why use an asynchronous framework where you need synchronous execution of work? Isn't it possible to just call work from process?