Add comments next to files in Linux

Question

I'm interested in simply adding a comment next to my files in Linux (Ubuntu). An example would be:

info user ... my_data.csv           Raw data which was sent to me.
info user ... my_data_cleaned.csv   Raw data with duplicates filtered.
info user ... my_data_top10.csv     Cleaned data with only top 10 values selected for each ID.

So sort of the way you can comment commits in Git. I don't particularly care about searching on these tags, filtering them etc. Just seeings them when I list files in a directory. Bonus if the comments/tags follow the document around as I copy or move it.

Answer 1

Most filesystem types support extended attributes where you could store comments.

So for example to create a comment on "foo.file":

xattr -w user.comment "This is a comment" foo.file

The attributes can be copied/moved with the file just be aware that many utilities require special options to copy the extended attributes.

Then to list files with comments use a script or program that grabs the extended attribute. Here is a simple example to use as a starting point, it just lists the files in the current directory:

#!/bin/sh
ls -1 | while read -r FILE; do
   comment=`xattr -p user.comment "$FILE" 2>/dev/null`
   if [ -n "$comment" ]; then
      echo "$FILE Comment: $comment"
   else
      echo "$FILE"
   fi
done

The xattr command is really slow and poorly written (it doesn't even return error status) so I suggest something else if possible. Use setfattr and getfattr in a more complex script than what I have provided. Or maybe a custom ls command that is aware of the user.comment attribute.