Pad numerical values in filename with three digit value using sed

Question

I am passing a filename into my bash script and cleaning the name using sed. A few sample files would be:

Test 01.txt
Test v2 01.txt

I would

Answer 1

Per your comment, yes I understand about debugging with that method, and that was my guess.

It's almost as easy, and doesn't require a cleanup step later on to move the closing lines and the "'" char up and down a list like below to debug (as an alternative solution).

j=$(
  echo "$j" \
  | sed '
    s/\///g
    s/_/ /g
    s/^\.//
    s/\[[^()]*\]//g
    s/([^()]*)//g
    s/#//g
    s/+/\ /g
    s/\.\././g
    s/\&/and/g
    s/\ -/-/g
    s/-\ /-/g
    s/-{2,}/-/g
    s/\.\././g
    s/'"'"'//g
    s/ {2,}/ /g
    s/\ \././g
' \
| awk '/[0-9]/{
   match( $0,/[0-9][0-9]*/ )
   begin=substr($0,1,RSTART); end=substr($0,RSTART+RLENGTH,length($0))
   num=substr($0,RSTART,RSTART+RLENGTH)
   printf("%s%03d%s", begin,num+0, end)
  }'
)

Edit It may be possible to double-triple up on the escaped single quotes, i.e. \\' or \\\', but I'm going with the tried and true s/'"'"'//g.

Unless you're using the original bourne shell on Solaris, AIX, HP, or other old-line unixen, join the 1990s ;-) and use the $( ...) construct for command substitution. Backquotes have been deprecated since at least 'The New Kornshell programming Language', published 1995.

I hope this helps.