appending to a directory in terminal

Question

I would like to append new files to an existing directory in terminal. So I'm using :

cp -r pathtodirectory/directory/ directory

but I do not want to overwrite, I just want to update. Any ideas?

Answer 1

find pathtodirectory/directory -maxdepth 1 -type f -exec sh -c \
    'for f; do ff="directory/$(basename $f)"; if [[ ! -f "$ff" ]]; then echo "Copying $f" && cp "$f" "$ff"; fi; done' sh {} +

LIMITATIONS:

• no spaces/glob characters in filenames