What are the best practices for handling file permissions in PHP scripts to avoid security risks?

File permissions in PHP scripts should be carefully managed to avoid security risks. It is important to set appropriate permissions on files and directories to prevent unauthorized access or modification. This can be done by using the chmod function in PHP to set specific permissions for files and directories.

// Set appropriate permissions for a file
chmod('example.txt', 0644);

// Set appropriate permissions for a directory
chmod('uploads', 0755);