Attempting to discover a command to copy files if the destination's (not source's) file has not been modified in the last hour.

  • 1
    There isn't a direct one. Could you modify your requirement to copy files only if the source is newer (has been modified more recently) than the target? – roaima Jul 25 '18 at 21:58
  • Sadly not. Is it possible to move files that have been modified in the last hour? If that is the case, I could do that, copy all the files then move the moved files back into their original location. – James Jul 25 '18 at 22:01

I know of no command that will precisely match your requirement. Something like this should work (remove the --dry-run when you're sure you're happy with the result; replace the --verbose with --quiet if you want it to run more silently):


comm -z -23 \
        <(find "$src" -type f -printf '%P\0' | sort -z) \
        <(find "$dst" -type f -mmin -60 -printf '%P\0' | sort -z) |
    rsync --dry-run --verbose --archive --from0 --files-from - "$src" "$dst"

It assumes relatively recent utilities that understand how to handle NUL-terminated lines. If necessary, and provided that you can guarantee that no filenames contain newlines, you could remove the three -z flags and rsync's --from0 and replace the \0 in the find commands with \n.

  • Awesome. Thank you! Not sure if this works yet, will give it a go when this is required. – James Jul 25 '18 at 22:36

If all your copies are to existing files, you can look at it the other way: overwrite local files if they are older than one hour. So, with the destination directory as the working directory:

find . -mindepth 1 -maxdepth 1 -type f -mmin +60 -exec cp /source/directory/{} . \;


  • find . -mindepth 1 -maxdepth 1 -type f -mmin +60 finds the local files that are over an hour old
  • -exec cp /source/directory/{} . \; overwrites them with their namesake from /source/directory
  • Thank you! I will give this a shot if roaima's answer doesn't work. – James Jul 25 '18 at 22:36

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