To make a copy of a file or folder in terminal is really simple and handy.
The command is cp and the syntax looks like this…
cp “/Volumes/LocalUSB/Photos/” “/Volumes/RemoteUSB/Photos/”
cp copy
What you want to copy and it’s location:
“/Volumes/LocalUSB/Photos/“
and the destination
“/Volumes/RemoteUSB/Photos/”
There are a few options and you add these right after you type cp:
n – Do not overwrite an existing file
p – Preserves attributes, including resource forks
R – When the source file is a directory and the path ends in with a slash (/) then the entire contents of the directory are copied
v – Causes files to be listed when copied
I strongly recommend running a time machine before backup playing around with this command.