*---------------------------------------------------------------------*
*       FORM CALL_SHELL_SCRIPT                                        *
*---------------------------------------------------------------------*
*       ........                                                      *
*---------------------------------------------------------------------*
*  -->  PAR_FILENAME                                                  *
*---------------------------------------------------------------------*
FORM call_shell_script USING par_filename.  

In the first session we can define TOP-OF-PAGE event as normally and we will insert the special wording replace the page count.

In the second session we will place this code at the last of program. This session will replace back the no. of last page to special wording that you define in the first session. 

*** Note: If the special wording is not in the first line of report, you can change the sentence ’READ LINE 1 OF PAGE SY-INDEX.’ to ’READ LINE X OF PAGE SY-INDEX.’ by X is the no. of line that you want to modify.

CALL FUNCTION ’KD_GET_FILENAME_ON_F4’ 
   EXPORTING 
    MASK = ’,*.txt,*.*’ 
    STATIC = ’X’ 
  CHANGING 
    FILE_NAME = LV_FILE.

Method 2 

     CALL FUNCTION ’F4_FILENAME’
       EXPORTING
         program_name  = syst-cprog
         dynpro_number = syst-dynnr
         field_name    

In ABAP/4, the event immidiately begins when the program is running. In general, these events is normally used in the report:

• INITIALIZATION
  This is the first event when the report generated. We can modify default value of selection screen.
• AT SELECTION-SCREEN
  If we want to verify input data before executing program, we will use this event. This event is triggered when user press Enter.
• START-OF-SELECTION
  This event is activated at the main process when the program is executed.
• END-OF-SELECTION
  This event is activated follow on START-OF-SELECTION event.