CopyDir recursively copies a directory tree, attempting to preserve permissions.

CopyFileContents that copies file contents and does Chown when needed to drop sudo privileges.

IsSymlink determines if the given path is a symbolic link.

Mkdir that does Chown when needed to drop sudo privileges.

MkdirAll that does Chown when needed to drop sudo privileges.

Symlink that does Chown when needed to drop sudo privileges.

WriteFile that does Chown when needed to drop sudo privileges.