How to delete multiple same characters from a file using bash script?-CodePudding

I have this script which removes the first periods from a file in order to unhide it. However, all it can do is remove the first period and not the succeeding periods, which makes the file still hidden. What I want to know now is how I can remove more than 1 periods at a time to unhide the file.

#!/bin/bash
period='.'
for i in $@; do
      if [[ "$i" == "$period"* ]] ; then
            mv "$i" "${i#"$period"}"
      else
            mv $i .${i}
      fi
 done

I have some knowledge in using grep and regex so I thought of using to remove a lot of them at a time but I cant really figure out if it is the correct way to go about it

CodePudding user response：

You can use the bash extended glob (pattern) to match one or more periods, combined with the ## parameter expansion to remove the longest leading match:

#!/usr/bin/env bash

# Turn on extended globs
shopt -s extglob

name=...foo
printf "%s -> %s\n" "$name" "${name## (.)}"

Or you can use a regular expression, combining looking for leading periods with capturing the rest of the name:

#!/usr/bin/env bash

# Note the quoted parameters to avoid many issues.
for i in "$@"; do
      if [[ "$i" =~ ^\. (.*) ]]; then
            mv "$i" "${BASH_REMATCH[1]}"
      else
            mv "$i" ".${i}"
      fi
 done