So if I had a cp -v operation fail, is the last file name it printed out the last successful file copy, or is it the failed partially copied file? If you had to ensure all files are copied correctly without overwriting anything, would deleting the last filename that was printed from the destination folder delete the partially copied file that the operation failed on?
Another way to check is to
strace cp testfile testfile2and the sequence in which the message is printed and operations performed can be studied.
It’s perhaps a lot to read, but linux tracing tools are worth learning!