There's a typo in arp.c: agrv instead of argv on line 107.

Onno van der Linden     c/o     frank@fwi.uva.nl (Frank van der Linden)
*** /usr/src/usr.sbin/arp/arp.c.orig	Sun Feb 26 10:28:51 1995
--- /usr/src/usr.sbin/arp/arp.c	Sun Feb 26 19:40:37 1995
***************
*** 105,109 ****
  			if (argc != 3)
  				usage();
! 			exit(file(agrv[2]));
  		case '?':
  		default:
--- 105,109 ----
  			if (argc != 3)
  				usage();
! 			exit(file(argv[2]));
  		case '?':
  		default: