bash_n_examples/bash/printf/printf2.sh

   1 num=`stty size | cut -d ' ' -f 2`
   2 char="█"
   3 string="string"
   4 lenstr="${#string}"
   5 space=`expr \( $num - $lenstr \) / 2`
   6 expr $space + $lenstr + $space
   7 printnum=`expr $lenstr + $space`
   8 line="$(printf "%${num}c" " ")"
   9 line="${line// /${char}}"
  10 echo -n "${line}"
  11 printf "%-${num}s" "$string"
  12 echo -n "${line}"
  13 printf "%${printnum}s\n" "$string"
  14 echo -n "${line}"
  15 printf "%${num}s" "$string"
  16 echo -n "${line}"