Function _clear_child_tid

components/lwp/lwp_pid.c:832–843

* @brief Clear child thread ID notification for parent process * * @param[in,out] thread Thread whose child tid needs to be cleared * * @note This function performs the following operations: * - Checks if clear_child_tid pointer is set * - Writes 0 to user-space memory location if set * - Wakes any futex waiters on that location * - Clears the thread's clear_child_t

 *       - Clears the thread's clear_child_tid pointer
 */
rt_inline void _clear_child_tid(rt_thread_t thread)
{
    if (thread->clear_child_tid)
    {
        int t = 0;
        int *clear_child_tid = thread->clear_child_tid;

        thread->clear_child_tid = RT_NULL;
        lwp_put_to_user(clear_child_tid, &t, sizeof t);
        sys_futex(clear_child_tid, FUTEX_WAKE, 1, RT_NULL, RT_NULL, 0);
    }
}

/**
 * @brief Terminates a lightweight process and cleans up its resources