PROCESS EVENTS permite a execução de outros eventos a qualquer momento dentro de um looping.

Exemplo
DEFINE BUTTON stop-it LABEL “STOP”.
DEFINE VARIABLE i AS INTEGER.

DEFINE VARIABLE stop-sel AS LOGICAL INITIAL FALSE.
DISPLAY stop-it.

ON CHOOSE OF stop-it
   stop-sel = TRUE.
ENABLE stop-it.

DO i = 1 TO 1000: 
  DISPLAY i VIEW-AS TEXT.
  PROCESS EVENTS.
  IF stop-sel
  THEN LEAVE.
END.

abs