Get or set file comment (Linux)

comment

#!/usr/bin/env sh

usage() {
  cat <<EOF
USAGE
  $(basename $0) FILENAME [COMMENT]

  Get or set file comment.

ARGUMENTS
  FILENAME
    The file to get or set comment on.

  COMMENT
    The comment to set. If not provided, get the existing comment if any.
EOF
}

comment_attr=user.xdg.comment
filename="$1"
comment="$2"

if [ -z "$filename" ]
then
  usage
elif [ -z "$comment" ]
then
  getfattr -n "$comment_attr" "$filename"
else
  setfattr -n "$comment_attr" -v "$comment" "$filename"
fi