Rename Multiple Files - Shell Geek

Automating Filename Changes with Bash Scripting

Imagine a scenario where a directory contains numerous files with incorrect naming conventions. For instance, you might need to substitute "test" with "prod" in every filename. This can be efficiently achieved using the "for" command within the bash shell, leveraging its powerful features.

This article will demonstrate how to perform text replacement within a variable during a "for" loop. The fundamental structure of the "for" command is as follows:

for var in ; do $var; done

Understanding the "for" Loop

The placeholder accepts any file matching pattern, such as "*" for all files or "*.txt" for text files. The placeholder represents any Linux command you wish to execute.

The specified command will be executed sequentially on each file that matches the defined pattern. Bash's variable handling capabilities further enhance this process.

Replacing Text Within Filenames

Instead of simply using the filename directly, like "mv $var", you can dynamically modify it using this syntax:

${var/originaltext/replacetext}

This allows for targeted text substitution within the filename variable.

Practical Example: Replacing "test" with "prod"

To apply this to our example, the following command can be used:

for f in *; do mv $f ${f/test/prod}; done

For each file matching the "*" pattern, bash will execute a command resembling this:

mv test.config prod.config

The Value of Shell Scripting

Proficiency in shell scripting proves exceptionally valuable when managing servers or organizing file systems. It can significantly reduce the time spent on tasks that would otherwise require manual intervention.

While numerous tools exist for bulk file renaming, understanding bash scripting provides a flexible and powerful solution for automating these processes.

Knowledge of the shell can save hours of manual work.