Backup pdf annotations edited with skim.app

backup_skim.sh

#!/bin/bash

tmp='/tmp/tmp.skim'

find . -type f -regex ".*\.pdf" | while IFS= read -r org; do
    dst=$(echo "$org" | sed 's/\.pdf$/.skim/')

    if skimnotes test "${org}"; then
        if [ -e "${dst}" ]; then
            # If .skim already exists
            skimnotes get "${org}" ${tmp}
            if ! diff -q "${tmp}" "${dst}" >/dev/null; then
                # Update .skim only if it is different
                mv "${tmp}" "${dst}"
                echo "${org}" "(updated)"
            fi
        else
            # If .skim does not exist
            skimnotes get "${org}" "${dst}"
            echo "${org}" "(new)"
        fi
    fi
done