do{

           sprintf(device,"%s%d",nit_dev,n++); sock=open(device,O_RDONLY);

    } while(sock<0 && errno==EBUSY);

    if(ioctl(sock,BIOCVERSION,(char *)&bv)<0) return(-2);

    if((bv.bv_major!=BPF_MAJOR_VERSION)||(bv.bv_minor<BPF_MINOR_VERSION))return(-3);

    strncpy(f.ifr_name,nic_name,sizeof(f.ifr_name));

    if(ioctl(sock,BIOCSETIF,(char *)&f)<0) return(-4);

    ioctl(sock,BIOCPROMISC,NULL);if(ioctl(sock,BIOCGBLEN,(char *)&size)<0) return(-5);

#endif

#ifdef IRIX

    struct sockaddr_raw sr; struct snoopfilter sf;

    int size=CHUNKSIZE,on=1; char *interface;

    if((sock=socket(PF_RAW,SOCK_RAW,RAWPROTO_SNOOP))<0) return(-1);

    sr.sr_family = AF_RAW; sr.sr_port = 0;

    if (!(interface=(char *)getenv("interface")))

    memset(sr.sr_ifname,0,sizeof(sr.sr_ifname));

    else strncpy(sr.sr_ifname,interface,sizeof(sr.sr_ifname));

    if(bind(sock,&sr,sizeof(sr))<0) return(-2); memset((char *)&sf,0,sizeof(sf));

    if(ioctl(sock,SIOCADDSNOOP,&sf)<0) return(-3);

    setsockopt(sock,SOL_SOCKET,SO_RCVBUF, (char *)&size,sizeof(size));

    if(ioctl(sock,SIOCSNOOPING,&on)<0) return(-4);

#endif

#ifdef SOLARIS