Sanitizes a filename replacing whitespace with dashes
Removes special characters that are illegal in filenames on certain operating systems and special characters requiring special escaping to manipulate at the command line. Replaces spaces and consecutive dashes with a single dash. Trim period, dash and underscore from beginning and end of filename.
The special characters are passed through the sanitize_file_name_chars filter before removing them from the file name, allowing plugins to change which characters are considered invalid. After sanitize_file_name() has done its work, it passes the sanitized file name through the sanitize_file_name filter.