Function sys_getpriority

components/lwp/lwp_syscall.c:1568–1589

* @brief Retrieves the priority of a process or process group. * * This system call returns the priority of a process or a process group, depending on * the value of the `which` argument. * * @param which The entity for which the priority is being requested. Possible values include: * - `PRIO_PROCESS`: Retrieves the priority of the process specified by `who`. * - `

 * @see setpriority(), getpid(), getppid()
 */
sysret_t sys_getpriority(int which, id_t who)
{
    long prio = 0xff;

    if (which == PRIO_PROCESS)
    {
        struct rt_lwp *lwp = RT_NULL;

        lwp_pid_lock_take();
        lwp = lwp_from_pid_locked(who);

        if (lwp)
        {
            rt_thread_t thread = rt_list_entry(lwp->t_grp.prev, struct rt_thread, sibling);
            prio = RT_SCHED_PRIV(thread).current_priority;
        }

        lwp_pid_lock_release();
    }

    return prio;
}

/**
 * @brief Sets the priority of a process, process group, or user.