Re: [Gumstix-users] RESUBMITTED: fping returning negative roundtrip times after I set the date

[Dave H. <dhy...@gm...>]

Hi Morgan,

\> If I use fping, now the roundtrip times are negative,
> like the example below...
>
> # ./fping -c 3 -e google.com
> google.com : [0], 84 bytes, 0.-115640228 ms

This seems to be a problem with the packet data coming from the
network stack. fping is taking a timestamp from the received packet,
and this timestamp doesn't seem to be adjusted based on the time of
day.

I threw some prints in timeval_diff and got this output on my FC5 box:
a->tv_sec = 1161700624
b->tv_sec = 1161700624
google.com : [2], 84 bytes, 114 ms (96.9 avg, 0% loss)

and this on my gumstix:
a->tv_sec = 1161700684
b->tv_sec = 9548
google.com : [2], 84 bytes, 105209 ms (105251 avg, 0% loss)

So the problem is that the b->tv_sec is using the original date/time.
The data that's used to calculate b->tv_sec originates with the data
in the recvfrom_wto call, which comes from the recvfrom call.

-- 
Dave Hylands
Vancouver, BC, Canada
http://www.DaveHylands.com/