17  * Sum bytes in file mod 2^16
25 	unsigned int sum;  in main()  local
36 					"sum: Can't open %s\n", argv[i]);  in main()
42 		sum = 0;  in main()
46 			if (sum&01)  in main()
47 				sum = (sum>>1) + 0x8000;  in main()
49 				sum >>= 1;  in main()
50 			sum += c;  in main()
51 			sum &= 0xFFFF;  in main()
56 				"sum: read error on %s\n",  in main()
60 		(void) printf("%05u %5lld", sum,  in main()