This program will scan a directory and replace invalid characters in filenames with an underscore. So for example if you had a file called ‘/file’ after running scandir the file will be named ‘_file’. This will allow you to again access files that for whatever reason have invalid characters in their names.
For example: ‘scandir /’ will scan the root directory, ‘scandir /bin’ would scan the /bin directory.
Note: this tool only scans the specified directory, not the whole filesystem.