前言部分
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正文部分
关于系统的消息类型：
写MESSAGE一定要加上TYPE
那么消息类型有几种呢
message types： "A", "E", "I", "S", "W", or "X"
One of the possible message types "A", "E", "I", "S", "W", or "X" must be specified
For messages displayed in a dialog box by default, the short text is still displayed as a dialog box.
Messages with the type "E" or "W" (except those for PBO and LOAD-OF-PROGRAM) are displayed as a dialog window if dtype contains "A" or "I".
Messages with the type "S" are always displayed in the status bar, regardless of the dtype.
The latter also applies to messages of the type "I" for PBO and LOAD-OF-PROGRAM.
Messages of the type "X" always cause a runtime error.
按照上面的顺序分析一下
A：Abend 异常终止 终止当前操作
E：Error 错误 系统等待 新输入数据
I： Infor 信息 处理回车之后 系统继续处理
S：Success成功 消息出现 在下一屏上
W：Warning警告 可以更改 输入数据或 通过按回车继续
X：EXIT 退出 退出操作 或返回上一层操作 通常是运行时错误
matinal