How do you find and delete files older than a specific date in a shell script?

In shell scripting, to locate and delete files older than a specific date, the find command is commonly used. This command is highly versatile for identifying files and directories that meet certain criteria, and it can be paired with the -exec option to perform actions on these items. Below is a practical example demonstrating how to delete files older than 30 days.

1. Determine the Target Directory: First, identify where the files you intend to operate on are stored. For this example, assume the directory is /path/to/directory.

2. Write the Script:

bash
#!/bin/bash

# Define directory path
TARGET_DIR="/path/to/directory"

# Define days, here 30 days as an example
DAYS=30

# Locate and delete files older than 30 days
find $TARGET_DIR -type f -mtime +$DAYS -exec rm -f {} +

echo "All files older than $DAYS days in $TARGET_DIR have been deleted."

Explanation:

• find $TARGET_DIR -type f：Identifies all files (excluding directories) within the specified directory $TARGET_DIR.
• -mtime +$DAYS：mtime refers to the last modification time of the file content, and +$DAYS specifies files modified more than $DAYS days ago.
• -exec rm -f {} +：Executes the rm -f command on each found file for deletion. Here, {} acts as a placeholder for the file name identified by find, and + indicates that rm is executed once for multiple files.

1. Run the Script: Save the script to a file, such as delete_old_files.sh, grant execute permissions, and execute it:

bash
chmod +x delete_old_files.sh
./delete_old_files.sh

This script safely removes all files in the specified directory that have not been modified for over 30 days. Adjust TARGET_DIR and DAYS as needed for your use case. To avoid accidental deletion of critical files, always test the script in a non-production environment before deployment.