status.i4.v = acl_register_user_exit_handler(callb_function.f.v

	This routine will register an exit handler that will be executed
	when the calling process is terminated.

	callb_function	address of function to be called as follows:
			callback(acl_data.s.r, callb_data.g.v)
			("acl_data" is a structure of type ACL_EXIT_DATA
			 which delivers the status of ACL at the time of
			 process termination.)
	[callb_data]	pointer to user-supplied data to be passed to
			callback function (default is NULL)

	This function returns status values as follows:

	CLIB_OK			success
	CLIB_DUPREQ		a function has already been registered

	This function requires the following include files:

	acl_h, acnet_errors.h

	Related functions:

	intro_acl, acl_unregister_user_exit_handler, acl_execute_c,
	acl_file_execute_c, acl_compile_c, acl_free_c, acl_file_read_c,
	acl_file_write_c, acl_read_symbol_c, acl_read_symbol_info_c,
	acl_read_symbol_names, acl_info_c, acl_cancel_requests_c,
	acl_set_symbol_c, acl_default_data_source_c, acl_log_file_c,
	acl_default_script_path_c, acl_script_is_executing,
	acl_register_host_request_func, acl_unregister_host_request_func,
	acl_translate_command_string, acl_file_read_description_c,

	C/C++ usage:

	int	status;
	acl_exit_handler_function	callb_function;
	void	*callb_data = (void *) NULL;

	status = acl_register_user_exit_handler(callb_function,callb_data);