When you write your first pop-up window program that is "output only" (ie: no input capable fields) you will probably get a result like this on your first attempt:
    ------------ Screen cursor goes to here when the "Companies"    |             pop-up window appears.    |

              DEMO01          Demonstration Panel                                                                                                                                       ..........................             Specify the following and press : COMP01  Companies      :                                             :                        :             Account number . . . . .        : Number Description     :                                             :  01    ACME ENGINEERING:             Account type . . . . . .        :  02    CONSOLIDATED ENG:                                             :  03    ACME WELDING    :             Company number . . . . .        :  04    DESIGN INC.     :                                             :                        :             Transaction amount . . .        :........................:
 

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This is clearly unacceptable, because the user has to move the screen cursor right across the screen and into the "Companies" pop-up window to select the desired company.
The simplest solution to this problem is: code the POP_UP command like this:
           POP_UP ....whatever.... CURSOR_LOC(*ATFIELD #COMPNO)
which will cause the pop-up window to appear like this with the screen cursor under 0 in "01 ACME ENGINEERING":

          DEMO01          Demonstration Panel                                                                                                                                              ...........................            Specify the following and press e: COMP01  Companies       :                                             :                         :            Account number . . . . .         : Number Description      :                                             :  01    ACME ENGINEERING :            Account type . . . . . .         :  02    CONSOLIDATED ENG :                                             :  03    ACME WELDING     :            Company number . . . . .         :  04    DESIGN INC.      :                                             :                         :            Transaction amount . . .         :.........................: 
 

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