hello I've been trying and failing to match the user agent string for the browser acl type. I would appreciate any help. I don't know exactly what squid sees as the user agent but a capture of the traffic shows the user agent header and I'm basing it on what I see there. The complicating fact is that a simple substring search won't work as there are multiple browsers with the same string. I wish to match the Windows and Mac OS X version of Safari. Its user agent string is shown as: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_4; en-us) AppleWebKit/533.18.1 (KHTML, like Gecko) Version/5.0.2 Safari/533.18.5\r\n Looking simply for "Safari" works but the same string is reported in Google's Chrome user-agent, which I don't want to match. I've tried things like ".*Version.* Safari.*" and including [0-9] groups for the version numbers, all to no avail. For comparison , on OS X: Chrome sends: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10_6_4; en-US) AppleWebKit/534.7 (KHTML, like Gecko) Chrome/7.0.517.41 Safari/534.7\r\n Camino: Mozilla/5.0 (Macintosh; U; Intel Mac OS X 10.6; en; rv:1.9.0.19) Gecko/2010081818 Camino/2.0.4 (like Firefox/3.0.19)\r\n Firefox: Mozilla/5.0 (Macintosh; U; Intel Mac OS X; en-US; rv:1.8.1) Gecko/20061010 Firefox/2.0\r\n I could invert my ACL Logic and match on the other browsers but I'd prefer a more direct way. Any suggestions much appreciated. thanks rolf.