File and Directory names

Dialects prior to LAN Manager 2.0 required that file and directory names adhere to the 8.3 name format. Names of this format consist of two parts: a basename of no more than eight characters, and an extension of no more than three characters. The basename and extension are separated by a "." (period). All characters are legal in the basename and extension except:

  • The space character (0x20)

  • "\/[]:+|<>=;?,*.

The LAN Manager 2.0 dialect introduced the SMB_FLAGS2_KNOWS_LONG_NAMES flag. If a client or server sets this flag in its messages, this indicates that they are not bound by the 8.3 name convention and support long file and directory names. Long names have MUST a total length of less than 255 characters. The following characters are illegal in a long name:

  • "\/[]:+|<>=;?,*

A "." (period) is treated as a delimiter of file name components. The 8.3 name format uses the period to separate the filename from the file extension.