On Sat, Jan 24, 2015 at 10:21 AM, <sohcahto...@gmail.com> wrote: > On Friday, January 23, 2015 at 2:50:12 PM UTC-8, Chris Angelico wrote: >> On Sat, Jan 24, 2015 at 9:38 AM, <sohcahto...@gmail.com> wrote: >> > Secondly, even if you find a module, keep in mind that the module probably >> > won't stay in Python land. It will probably call an external utility >> > itself. >> > >> > If you REALLY wanted to check it without calling an external utility, you >> > could connect to port 67 and see what happens, but that could cause >> > problems. >> >> We're talking UDP here, so there's no "connect to" concept. You have >> to send a packet and listen for a reply, and that might have >> consequences (eg if you send a DHCPDISCOVER just to find out if >> there's a DHCP server, you potentially cause a temporary IP >> allocation). >> >> Reading from /proc or running an external program would be the best >> ways to find out. >> >> ChrisA > > I forgot that DHCP uses UDP. My mistake.
Yeah, it's usually easier to probe a TCP service. You can either connect to it, or - often - simply try to bind to the same port, as you'll usually get an error. Not always, though, so connecting is the reliable test. ChrisA -- https://mail.python.org/mailman/listinfo/python-list
