Where am I? (Geolocation, Emacs, Perl)

This is one of those "surely there is some generic utility that is better than the quick and dirty thing I have whipped up" questions. As in, I know how to do this in several ad-hoc ways, but would love to use a standard. BRIEF: I am looking for reasonably standard and ubiquitous tools to determine my present geographical location. Callable from Linux/UNIX command line, Perl, Emacs, etc. DETAIL: A trivial situation inspires this question (but there are undoubtedly more important applications): I use emacs org-mode, often to record a log or diary. I don't actually use the official org-mode diary much - mainly, I drop timestamps in an ordinary org-mode log, hidden in metadata that looks like a link. ``` [[metadata: timestamp="<2014-01-04 15:02:35 EST, Saturday, January 4, WW01>" <location location="??" timestamp="??"/>][03:02 PM]] ``` As you can see, I long ago added the ability to RECORD my location. But hitherto I have had to set it manually. I am lazy, and often neglect to set the location manually. (Minor note: I recorded the last time I manually set the location, helpful when I move and neglect to manually change my location. I would much prefer to have code that automatically infers my location. Particularly since I have been travelling quite a bit in the last month, but probably more useful for the half-dozen or so locations I move between on a daily basis: home, work, oceanside, the standard restaurants I eat working lunch or breakfast in. I can figure my location out using any of several tools, such as Where Am I - See your Current Location on Google Maps - ctrlq.org/maps/where/ http://www.wolframalpha.com/input/?i=Where+am+I%3F Perl CPAN packages such as IP::Location - to map an IP address to a location - note: doesn't necessarily work for a private IP address, behind NAT - but can combine with traceroute and heuristics such as looking at WiFi SSIDs, etc. I have already coded something up. But... there's more depth to this than I have coded. None of the techniques above is perfect - e.g. I may not have net.connectivity, etc. Some are OS specific. If there is already some open source facility, I should use that. Therefore my question: is there any reasonably ubiquitous geo location service? My wishlist Works cross OS - Cygwin - Linux - Android? OS-X? (just use OS standard) - e.g. tries to exec a command like Windows netsh, and if that fails... Command line utility - Perl, etc. - callable in emacs - because that is where I want to use it - but I am sure that I would want to be able to use it in other places. Can connect to widely available standard geolocation services - e.g. Perl CPAN IP::Location, IP->country/city/... - e.g. Google, etc., infer geographical location from browser Works even when cannot connect to standard geolocation services, or the Internet - e.g. cache last location - e.g. ability to associate a name with a private network environment - e.g. if in a lab that is isolated from network - or at home, connected to WiFi, but broadband down - e.g. look at wifi SSID Customizable - can use information that is NOT part of any ubiquitous geolocation database - e.g. I may recognize certain SSIDs as being my home or office. Learned - Knows (or can learn) that some SSIDs are mobile, not geographically fixed (e.g. the mobile hotspot on my phone) - but some are (mainly) geographically fixed (e.g. WiFi at home connected to cable modem) Learning - can override incorrect inferences (geo databases sometimes wrong, esp. VPN) - can extend or make precise - I wouldn't mind being able to write rules - but even better if some inference engine maintains the rules itself. - e.g. if I correct the location, make inferences about SSID coordinates used for the faulty inference Heuristics - Windows 7 "netsh wlan show interfaces" - Windows / Cygwin ipconfig - *IX ifconfig - traceroute / tracert - reverse IP lookup Caching - to avoid expensive lookups - but cache is NOT global - can be done per app - some apps may want to bypass the cache - others can use old data