AC_FLUSH_CALL_INTERNAL is a standard SAP function module that performs functionality. This is available within standard R/3 SAP systems depending on version and release level.
Below are the pattern details for this FM showing its interface including any import, export and tables parameters. There is also a list of Exceptions and for your convenience any standard documentation available. All this information and more can also be viewed if you enter the function module name AC_FLUSH_CALL_INTERNAL into the relevant SAP transaction such as SE37 or SE80.
CALL FUNCTION 'AC_FLUSH_CALL_INTERNAL' " * EXPORTING * system_flush = " c IMPORTING message_nr = " sy-subrc message_text = " sy-msgli * TABLES * xml_data_stream = " * CHANGING * xml_data_string = " string EXCEPTIONS SYSTEM_FAILURE = 1 " CALL_METHOD_FAILED = 2 " SET_PROPERTY_FAILED = 3 " GET_PROPERTY_FAILED = 4 " RFC_QUEUE_FAILED = 5 " XML_DATA_FAILED = 6 " UNKNOWN_ERROR = 7 " COMMUNICATION_FAILURE = 8 " GUI_NO_MODE_AVAILABLE = 9 " . " AC_FLUSH_CALL_INTERNAL