use strict; use warnings; $/='Traceroute:'; while(){ print "wanted $1, arrived at $2\n" if /traceroute to ((?:\d+\.){3}\d+).*\D((?:\d+\.){3}\d+)/s && $1 ne $2; } __DATA__ Traceroute: 10 1291134800 1291134792 1291134792 GoogleDNS 0.media.collegehumor.com 92.123.72.112 traceroute to 92.123.72.112 (92.123.72.112), 30 hops max, 60 byte packets 1 * * * 2 134.2.205.30 0.765 ms 1.125 ms 1.428 ms 3 134.2.250.254 0.612 ms 0.701 ms 0.695 ms 4 129.143.135.33 0.515 ms 0.516 ms 0.510 ms 5 129.143.1.149 1.014 ms 1.012 ms 1.010 ms 6 129.143.1.166 1.036 ms 0.821 ms 0.808 ms 7 129.143.1.130 274.286 ms 274.265 ms * 8 80.81.192.28 7.246 ms 6.913 ms 6.896 ms 9 92.123.72.0 7.319 ms 7.311 ms 7.297 ms Traceroute: 12 1291134800 1291134792 1291134792 LocalDNS 0.media.collegehumor.com 212.201.100.184 traceroute to 212.201.100.184 (212.201.100.184), 30 hops max, 60 byte packets 1 * * * 2 134.2.205.30 0.774 ms 1.121 ms 1.426 ms 3 134.2.250.254 0.635 ms 0.716 ms 0.709 ms 4 129.143.135.33 0.584 ms 0.583 ms 0.579 ms 5 129.143.1.149 0.951 ms 0.948 ms 0.942 ms 6 188.1.233.229 1.042 ms 0.969 ms 0.962 ms 7 188.1.145.77 4.665 ms 4.804 ms 4.826 ms 8 188.1.146.50 4.815 ms 4.890 ms 4.841 ms 9 188.1.145.73 7.071 ms 7.202 ms 7.241 ms 10 188.1.145.69 9.976 ms 10.001 ms 9.441 ms 11 212.201.100.184 9.289 ms 9.259 ms 9.276 ms