ctrl-c doesn't reliably kill ping

Frank Farance frank@farance.com
Tue Mar 15 00:46:00 GMT 2016

I have been having this problem with "ping".  If I "ping" a location that 
doesn't exist, then "ping" just hangs and cannot be killed via "kill -KILL [pid]".

A little digression, so you understand the background ... The workstation I am 
doing this from is connected to a Verizon router to their FIOS network.  Now the 
reason I mention this is that the router's DNS (via DHCP to my workstation) is, which I presume is forwarded from the router upstream to Verizon's 
DNS caches.  So if I type the URL http://something.that.doesnt.exist in my 
browser, rather than getting a Hostname Not Found error (at the name resolution 
level), it actually loads up a page saying "something.that.doesnt.exist" isn't 
found and then I have a Yahoo set of search results on things matching the 
broken hostname.

So all of this is normal ISP stuff: they actually resolve unknown addresses to 
their own website (which is

Ok, ending the digression ....

Back to the problem, so when I type

$ ping some.unknown.host

according to "ping", the hostname resolves to (as per the 
explanation above), but I cannot kill "ping".  I tried "ping" with a limited 
packet size and count so, in theory, "ping" would die on its own after 10 
packets, such as:

$ ping some.unknown.host 50 10

but it still hangs rather than timing out.  If I ping to some actual IP address 
that is unresponsive (route-able to the last subnet, but dies on the floor at 
the end), then I can kill via ctrl-c.  My only solution to the hanging "ping" is 
to kill the terminal window.

Any suggestions on:

- Why "ping" behaves this way?
- How to avoid this problem?

Thanks, in advance.


Frank Farance, Farance Inc.    T: +1 212 486 4700   M: +1 917 751 2900
mailto:frank@farance.com       http://farance.com
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