Linux: How to read through all files (checking a backup)

After finishing a backup to a USB stick, I like to verify that all is in place by reading through all files. Using the “tar” utility with verbose file output seemed to be a good idea. But…

Don’t

$ tar -cv . > /dev/null

For whatever reason, the files aren’t really read. Only the names of the files are printed.

It’s a bit of a mystery to me how the optimization was possible, but the time it took to complete this was way too short (using a USB stick flash)

Do

$ tar -cv . | cat > /dev/null

This, on the other hand, forces reading through the files