Rename multiple files

This guide provides instructions on how to create a Bash script to rename multiple files. This script also allows users to provide custom settings and options.

Overview

The script allows you to rename files in a directory based on your specified pattern. It’s highly configurable and includes error checking to prevent common mistakes.

Prerequisites

This guide assumes you have the following:

• A Linux operating system with a Bash shell environment.
• Basic knowledge of Bash scripting, such as creating, editing, and executing scripts.
• Basic knowledge of the mv command, used to rename files.

Script Structure

Let’s break down the script into various sections:

1. Shebang: The shebang #!/bin/bash at the beginning of the script informs the system that the script is to be executed by the Bash shell.
2. Variable Declaration: Here we declare variables that are used in the script.
3. Usage Function: This function provides information on how to use the script.
4. Error Handling: This section checks for any potential errors that may occur during script execution.
5. Main Logic: The main logic of the script where the renaming of files happens.

Creating the Bash Script

Below is the entire bash script with comments explaining each section:

#!/bin/bash

# Variable Declaration
DIR=""        # Directory to perform renaming
PATTERN=""    # Pattern of files to match
PREFIX=""     # Prefix to add to the files
SUFFIX=""     # Suffix to add to the files
DRY_RUN=0     # Dry run flag

# Usage Function
usage() {
  echo "Usage: $0 [-d directory] [-p pattern] [-P prefix] [-s suffix] [-n]"
  echo
  echo "Options:"
  echo "  -d directory : Directory to perform renaming"
  echo "  -p pattern   : Pattern of files to match"
  echo "  -P prefix    : Prefix to add to the files"
  echo "  -s suffix    : Suffix to add to the files"
  echo "  -n           : Perform a dry run without executing"
  exit 1
}

# Parse Command Line Arguments
while getopts "d:p:P:s:n" OPTION; do
  case $OPTION in
  d)
    DIR=$OPTARG
    ;;
  p)
    PATTERN=$OPTARG
    ;;
  P)
    PREFIX=$OPTARG
    ;;
  s)
    SUFFIX=$OPTARG
    ;;
  n)
    DRY_RUN=1
    ;;
  ?)
    usage
    ;;
  esac
done

# Error Checking
if [[ -z "$DIR" || -z "$PATTERN" ]]; then
  echo "ERROR: Directory and pattern are mandatory."
  usage
fi

if [ ! -d "$DIR" ]; then
  echo "ERROR: Directory $DIR does not exist."
  exit 1
fi

# Main Logic
for FILE in "$DIR/$PATTERN"; do
  NEW_FILE="${DIR}/${PREFIX}${FILE##*/}${SUFFIX}"

  echo "Renaming $FILE to $NEW_FILE"

  if [ $DRY_RUN -eq 0 ]; then
    mv "$FILE" "$NEW_FILE"
  fi
done

Using the Script

To use this script, follow these steps:

1. Save the script in a file, such as rename_files.sh.
2. Make the script executable by running chmod +x rename_files.sh.
3. Run the script with your desired options. For example, to add a prefix new_ to all .txt files in the /tmp directory, run:

./rename_files.sh -d /tmp -p '*.txt' -P new_

To perform a dry run without actually renaming files, use the -n option:

./rename_files.sh -d /tmp -p '*.txt' -P new_ -n

This script is flexible and customizable, meeting a variety of file renaming needs. If you encounter any issues, refer back to this documentation to understand the functionality and usage of the script.