What are the best practices for handling file permissions in PHP when dealing with safe mode restrictions?

When dealing with safe mode restrictions in PHP, it is important to handle file permissions properly to ensure that your application can still access and modify files as needed. One of the best practices for handling file permissions in this scenario is to use the `chmod()` function to set the appropriate permissions on files and directories before attempting to read from or write to them.

// Set file permissions using chmod() function
$filename = 'example.txt';
$permissions = 0644; // Set read and write permissions for owner, read-only for others

if (file_exists($filename)) {
    chmod($filename, $permissions);
} else {
    echo "File does not exist.";
}