rem: s_unlock_at(ml->sems, MS_SEM_SENT);
add: lock_release(&ml->sem_sent);
context: int msg_list_set_flag(msg_list ml, int mid, int fl){	msg_list_el p0;			if(!ml || mid==0)		goto errorx;		s_lock_at(ml->sems, MS_SEM_SENT);	p0 = ml->lsent;	while(p0)	{		if(p0->msgid==mid)		{			p0->flag |= fl;			DBG("MSILO: msg_list_set_flag: mid:%d fl:%d\n", p0->msgid, fl);			goto done;		}		p0 = p0->next;	}done:	s_unlock_at(ml->sems, MS_SEM_SENT);	return MSG_LIST_OK;errorx:	return MSG_LIST_ERR;}