PCAN_USBPRO_MSG_HEADER_LEN
pm->rec_ptr = pm->u.rec_buffer + PCAN_USBPRO_MSG_HEADER_LEN;
pm->rec_buffer_len = PCAN_USBPRO_MSG_HEADER_LEN;
if (actual_length < PCAN_USBPRO_MSG_HEADER_LEN) {
if (buffer_size < PCAN_USBPRO_MSG_HEADER_LEN)