Bash script to pad file names

(foo1, foo2, ..., foo1300, ..., fooN)

(foo00001, foo00002, ..., foo01300, ..., fooN)

for f in foo[0-9]*; do mv $f `printf foo%05d ${f#foo}`; done

for i in ((i=1; i<=N; i++)) ; do mv foo$i `printf foo%05d $i` ; done

rename 's/d+/sprintf("%05d",$&)/e' foo*

for file in foo*; do
  newnumber='00000'${file#foo}      # get number, pack with zeros
  newnumber=${newnumber:(-5)}       # the last five characters
  mv $file foo$newnumber            # rename
done

#!/bin/bash

# some test data
files="foo1
foo2
foo100
foo200
foo9999"

for f in $files; do
    prefix=`echo "$f" | cut -c 1-3`        # chars 1-3 = "foo"
    number=`echo "$f" | cut -c 4-`         # chars 4-end = the number
    printf "%s%04dn" "$prefix" "$number"
done

#!/bin/bash
for file in foo[0-9]*.png; do
  # strip the prefix ("foo") off the file name
  postfile=${file#foo}
  # strip the postfix (".png") off the file name
  number=${postfile%.png}
  # subtract 1 from the resulting number
  i=$((number-1))
  # copy to a new name in a new folder
  cp ${file} ../newframes/$(printf foo%08d.png $i)
done