Gianluca Varenni schrieb:
I just uploaded a new version of the spec here
http://www.winpcap.org/ntar/draft/PCAP-DumpFileFormat_ts.html
I tried to spedify the timestamps better and renamed if_tsaccur into 
if_tsresol.
Let me know if you think it makes more sense.
  
Yes it does, however still can be improved IMHO :-)
I would refer to "Unix time" only if it really represents the *seconds* 
til 1/1/1970 - and this isn't the case here. I wouldn't repeat the whole 
if_tsresol description here (to avoid duplication and the field 
description is already pretty long).
"Timestamp (High) and Timestamp (Low): high and low 32-bits of a 64-bit 
quantity representing the timestamp. The timestamp is a single 64-bit 
unsigned integer representing the number of units since 1/1/1970. The 
unit of this field is specified by the 'if_tsresol' option (see Figure 9 
(Interface Description Block format.) 
<http://www.winpcap.org/ntar/draft/PCAP-DumpFileFormat_ts.html#formatidb>) 
of the Interface Description block referenced by this packet. E.g. if 
the value of 'if_tsresol' is 9, the unit is 10^-9 nanoseconds, so the 
64-bit timestamp is simply the number of nanoseconds since 1/1/1970. 
Please note that differently from the libpcap file format, timestamps 
are not saved as two 32-bit values accounting for the seconds since 
1/1/1970 and microseconds of the day. They are a single 64-bit quantity 
saved as two 32-bit words."
I guess in future we will need a new field in IDB, something like 
"if_tsformat" (or so) to specify libpcap like or completely different 
timestamp formats - I guess that's the same conclusion Stephen Donelly 
may have. But we can do this later when the problem really arises ;-)
Regards, ULFL