标准语法如下：
CALL SCREEN dynnr
[STARTING AT col1 lin1
[ENDING AT col2 lin2]].
"The upper left corner of the dialog window is determined by the "values col1 and lin1 for column and line.
"he lower right corner is set automatically or you can use col2 and "lin2 to specify it after ENDING AT.
实际应用举例：
*调用弹框屏幕
CALL SCREEN 9001 STARTING AT 30 5 ENDING AT 100 15 .
对话框窗口的左上角由列和行的值col1和lin1确定。此例中上边距为5，左边距为30.
右下角是自动设置的，也可以使用col2和lin2在ENDING AT之后指定。
标签：SCREEN,col2,lin2,lin1,ENDING,Window,CALL From： https://www.cnblogs.com/1502762920-com/p/17247114.html