Int 21 Fn 5FB1  - Lantastic - Get Shared Directory Information             [N]

   AX = 5FB1h
   DS:SI -> 64-byte buffer for link description
   ES:DI -> ASCIZ machine and shared directory name in form
        "\\machine\shared-resource"

Return: CF clear if successful
       CX = access control list privileges for requesting user (see #1431)
   CF set on error
       AX = error code

Bitfields for LANtastic access control list:
Bit(s) Description (Table 1431)
 4 (I) allow expansion of indirect files
 5 (A) allow attribute changing
 6 (P) allow physical access to device
 7 (E) allow program execution
 8 (N) allow file renaming
 9 (K) allow directory deletion
 10    (D) allow file deletion
 11    (L) allow file/directory lookups
 12    (M) allow directory creation
 13    (C) allow file creation
 14    (W) allow open for write and writing
 15    (R) allow open for read and reading