Untitled

sh shell script of working with for loop
for d in `ls -1 $IMAGE_DIR | egrep "jpg$"`
do
  pgm_file=$IMAGE_DIR/`echo $d | sed 's/jpg$/pgm/'`

  echo "file  $pgm_file";
done

end_of_line=""
for d in "$IMAGE_DIR"/*.jpg
do
  file=$( basename "$d" )
  printf "file %s; %s" "$file" "$end_of_line"
  if [[ -z "$end_of_line" ]]; then
    end_of_line=$'n'
  else
    end_of_line=""
  fi

  pgm_file=${d%.jpg}.pgm
  # do something with "$pgm_file"
done

for d in "$IMAGE_DIR"/*jpg; do
  pgm_file=${d%jpg}pgm
  printf '%s;n' "$d"
done |
  awk 'END {
        if (ORS != RS)
          print RS
          }
       ORS = NR % n ? FS : RS
       ' n=2

echo -n "something; "
[[ -n "$oddeven" ]] && oddeven= || { echo;oddeven=x;}

[[ "$((n++%3))" = 0 ]] && echo