如何返回standard API 的错误信息

lv_msg_count :  为API返回参数,为消息的个数。

根据消息的具体情况，循环次数要做相应调整。加大次数，消息内容就多，反之则少.
IF lv_msg_count > 0 THEN 
        lv_mesg := chr(10) ||
                  substr(fnd_msg_pub.get(fnd_msg_pub.g_first, fnd_api.g_false),
                         1,
                         512);
        FOR i IN 1 .. (lv_msg_count - 3) LOOP
          lv_mesg := lv_mesg || chr(10) ||
                    substr(fnd_msg_pub.get(fnd_msg_pub.g_next, fnd_api.g_false),
                           1,
                           512);
        END LOOP;
END IF;
fnd_msg_pub.delete_msg();