APP_LVL
igp->igm_level = APP_LVL;
for (i = MEDIA_LVL; i < APP_LVL; i++) {
icp->igm_level != APP_LVL) {
int (*headerlen[APP_LVL])(struct inetgram *);
int (*input[APP_LVL])(int);
int (*output[APP_LVL])(int, struct inetgram *);
int (*close[APP_LVL])(int);
in_gram->igm_level = APP_LVL;
in_gram->igm_level = APP_LVL;