제가 특정화면 데이타를 일정 시간별(예를 들어30초마다 재조회)로 다시 refresh 하고 싶어서 관련 소스를 찾아봤더니 아래와 같은 소스가 있던데

아래 소스중

CALL FUNCTION 'Z_WAIT_30_SECS'
   STARTING NEW TASK 'IF'
   PERFORMING START_REFRESH ON END OF TASK.

여기에서 STARTING NEW TASK 'IF' 이게 무슨 의미인지 이해가 잘 안되네요.  IF는 모가 들어가야 되는 거죠

제가 초보라 쉬운 설명 부탁드려요...

FUNCTION Z_WAIT_30_SECS.

DATA: ZTIME LIKE SY-UZEIT.

GET TIME.

ZTIME = SY-UZEIT + 30.

DO.
  GET TIME.
  IF SY-UZEIT >= ZTIME.
     EXIT.
   ENDIF.
ENDDO.

ENDFUNCTION.

Then create this test program.

REPORT ZREFRESH LINE-SIZE 132 no standard page heading.

DATA: ZNUM LIKE SY-TABIX.

GET TIME.
WRITE: /01 'Update Number:', ZNUM, SY-UZEIT.

CALL FUNCTION 'Z_WAIT_30_SECS'
   STARTING NEW TASK 'IF'
   PERFORMING START_REFRESH ON END OF TASK.

AT USER-COMMAND.
IF SY-UCOMM = 'REFR'.

   SY-LSIND = SY-LSIND - 1.
   ADD 1 TO ZNUM.
   GET TIME.
   WRITE: /01 'Update Number:', ZNUM, SY-UZEIT.

   CALL FUNCTION 'Z_WAIT_30_SECS'
     STARTING NEW TASK 'IF'
     PERFORMING START_REFRESH ON END OF TASK.

ENDIF.

*----------------------------------------------------------------
* Program Subroutines
*----------------------------------------------------------------
FORM START_REFRESH USING TASKNAME.
* The SET USER-COMMAND initiates the communication back to the program
  SET USER-COMMAND 'REFR'.