taglinefilesource code
ar_pln1965drivers/net/arcnet.cif (arp->ar_hln==1 && arp->ar_pln==4)
ar_pln1985drivers/net/arcnet.carp->ar_hln,arp->ar_pln);
ar_pln77include/linux/if_arp.hunsigned char  ar_pln;    /* length of protocol address  */
ar_pln388net/ipv4/arp.carp->ar_pln = 4;
ar_pln622net/ipv4/arp.carp->ar_pln != 4)
ar_pln238net/ipv4/rarp.c|| rarp->ar_pln != 4)