On a sunny day (Mon, 30 Jul 2018 20:07:00 +1200) it happened
nospam.Henri.Derksen@f1208.n280.z2.binkp.net (Henri Derksen) wrote in
:

>Hello Jan,
>
>JP> You are copying on a raspi???
>
>Yes, why not, I do not have another Linux machine.
>
>JP> Using external card reader with 2 slots?
>
>External card reader yes, but NOT using the 2 slots at the same time.
>The source is the internal SDcard slot: /dev/mmcblk0
>The destination is /dev/sda


OK, to make a long story short:

  Do Not Do That

When you make copy from a running system to an other card,
then the source changes while the copy is being made.

Links may be changed, log files may be appended, or created,
data may be changed.

So the new copy will likely not run, and even if it does it WILL contain
errors and inconsistencies.

The right way is stop the raspi (type poweroff in a terminal perhaps) and do
the copy
on an other system.

--- SoupGate-Win32 v1.05