Errors during expire

[Kiernan, Alex]

We've a transit box which persists in panicing every few days (the
vendor believes hardware...), but every time we end up having to fix
the history file as it ends up with truncated lines or a spurious
Hole, or...

I was going to add an option to expire to ignore error lines in the
history file, but then I wondered if the right approach was to always
ignore errors and just fix any problems (logging them as you go).

Thoughts?

-- 
Alex Kiernan, Principal Engineer, Development, THUS plc