Subject: Re: libpcap and FDDI header fdd_ph[3] alignment: bug, or not?
To: None <>
From: Matt Thomas <>
List: tech-net
Date: 05/16/2000 08:10:37
At 08:37 PM 5/15/2000 -0700, Jonathan Stone wrote:

>In rev 1.6 of sys/net/if_fddi.h, we prepended the following to
>struct fddi_header:
>         u_char  fddi_ph[3];             /* makes the FDDI header 16 bytes */
>the commit message syas this is done to avoid alignment problmes.

I guess it depends on who you want to be compatible with.
I decided to be compatible with Digital UNIX and ULTRIX (which
also have fddi_ph).

Without the fix, tcpdump and other bpf utilities would need to be
changed to be able to deal unaligned FDDI packet data.  It was easier
to fix the fddi header than all the utilities.