ajmcello <ajmcello78(at)gmail(dot)com> writes:
> The only downside with adding o to tar that I can see is if it isn't
> supported by a non-GNU version of tar.
It's required by the Single Unix Spec
http://www.opengroup.org/onlinepubs/007908799/xcu/tar.html
(although that specifically disallows the ordering "oxf" that you
suggest) and I see it in tar on HPUX 10.20, which ought to be about
ancient enough for anybody.
regards, tom lane