How can PHP beginners avoid using incorrect functions like fopen when trying to open directories?

PHP beginners can avoid using incorrect functions like fopen when trying to open directories by using the correct function specifically designed for opening directories, which is opendir(). This function allows users to open directories and read their contents without causing errors or unexpected behavior.

// Correct way to open a directory using opendir()
$dir = "/path/to/directory";
if (is_dir($dir)) {
    $handle = opendir($dir);
    while (false !== ($file = readdir($handle))) {
        echo "$file\n";
    }
    closedir($handle);
} else {
    echo "Directory not found.";
}