CleanFilename strips all possibly suspicious characters from a filename WARNING: NOT suiteable for pathnames as slashes will be stripped as well!.

CleanPath resolves common aliases in a path and cleans it as much as possible.

IsDir checks if a certain path exists and is a directory https://stackoverflow.com/questions/10510691/how-to-check-whether-a-file-or-directory-denoted-by-a-path-exists-in-golang.

IsEmptyDir checks if a certain path is an empty directory.

IsFile checks if a certain path is actually a file.

Shred overwrite the given file any number of times.

Umask extracts the umask from env.