USE_PACKET_TIMESTAMP

[Matthew Selsky]

On Thu, Jun 08, 2017 at 12:26:21AM -0700, Hal Murray via devel wrote:
> Can anybody confirm that Solaris really doesn't have time stamps?  I thought 
> we decided that all modern OSes did.  That's why we could rip out the SIGIO 
> stuff.
> 
> I took a quick google and couldn't find any mention of anything that looked 
> like a time stamp in a Solaris man page for setsockopt.  But some of the 
> stuff I was looking at was surprisingly old.
> 
> If Solaris doesn't support time stamps, I would expect ntp_packetstamp to die 
> on a #error.  What happened with it?  If it does support time stamps, how are 
> we supposed to read them?  There are a bunch of CMSG macros over in 
> ntp_packetstamp.  They are useless without those missing symbols so it should 
> have barfed there too.

Newer versions of Solaris support SO_TIMESTAMP per:

https://docs.oracle.com/cd/E19957-01/820-0724/gcoqs/index.html
http://www.theptpguy.net/posts/2017/05/25/ptpd-on-legacy-systems-solaris-10-part-1-how-we-got-there
https://docs.oracle.com/cd/E36784_01/html/E36875/setsockopt-3socket.html#REFMAN3Bsetsockopt-3socket

This matches what I see in the Solaris 11u3 VM that I have connected to Buildbot.

Thanks,
-Matt