cp-date

#!/usr/bin/env bash
usage() { echo -e "Make copy of file with last change date at end.\nUSAGE: $0 myfile # makes myfile.YYYY-MM-DD"; }
[[ $# -eq 0  || $* =~ ^-+h ]] && usage && exit 1

# move if first arg is --mv
cp='cp'
[[ "$1" == '--mv' ]] && cp='mv' && shift 1

while [ $# -gt 0 ]; do
  infile="${1:?file to copy}"; shift
  [ ! -r "$infile" ] && warn "Bad file: '$infile'" && continue
  [[ ${infile} =~ /$ ]] && infile=${infile::-1}

  newname=$infile.$(find "$infile" -maxdepth 0 -printf '%CF')
  [ -r "$newname" ] && warn "$newname aleady exists!. remove and rerun to replace" && continue

  # handle directory copy (recursive) [added 20251024]
  args=()
  [[ $cp == "cp" && -d "$infile" ]] &&
     warn "# cp on dir '$infile'; running 'cp -r'. hope that's what you want" && args=(-r)

  dryrun $cp "${args[@]}" "$infile" "$newname"
done