Re: how to upgrade a whole machine ...

[Aleksey Cheusov <cheusov%tut.by@localhost>]

 >>     The 'skip pkg_summary if newer binary package' is not a failsafe
 >>     option - it can fail if a package has been delete or

You can forget my previous request for running external program in
case there are binaries newer than summary.

ALWAYS running pkg_update_summary before pkg_chk is better/more
correct solution.

You can leave pkg_chk as it is. Though, as you already noted, checking
for 'summary is more recent than all binaries' is not fully correct.

-- 
Best regards, Aleksey Cheusov.