The enum class type directory_options is a bitmask type ([bitmask.types]) that specifies bitmask constants used to identify directory traversal options, with the meanings listed in Table [tab:enum.directory_options].
| Name | Meaning |
| none | (Default) Skip directory symlinks, permission denied is an error. |
| follow_directory_symlink | Follow rather than skip directory symlinks. |
| skip_permission_denied | Skip directories that would otherwise result in permission denied. |