OVERVIEW
 File System Services Overview
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 Description

  The File System Services APIs allow an application to retrieve directory
  and volume information.  With these APIs the programmer can create, rename,
  and delete directories, modify a directory's maximum rights mask, add and
  delete trustees, allocate and deallocate directory handles, etc.

  $TABLES ACCESSED BY FSS$

  The workstation shell and file server maintain tables used by the FS.

  A Directory Table holds information about a file servers directories
  and directory structure and is maintained by the file server.  To do this
  the table hold three different node entries.  They are directory, file
  and trustee nodes.  The directory node holds the directory name, attribute
  byte, maximum rights mask, creation date, creator object ID, parent
  directory link, and trustee node link, if any.  The file node holds the
  filename, attribute byte, extended attribute byte, filesize, date created,
  date last accessed, date last updated, last archive date, owner object ID,
  and link to parent directory node.  The trustee node holds the object IDs
  of up to five trustees, corresponding rights masks, link to parent
  directory node, and a link to the next trustee node, if there are more
  than five trustees.

  A file server maintains a Directory Handle Table (DHT) for each workstation
  logged.  Any of the 255 entries (1-255) can be set to point to a volume or
  path.  Workstations have three corresponding tables that relate to the DHT.
  Each table holds 32 records, corresponding to the permanent (A-Z) and
  temporary ([,\,],,_,') drive letters.  The Drive Handle Table holds a
  directory handle index into the file servers DHT.  A Drive Flag Table holds
  info indicating if the drive is allocated, permanent or temporary, local or
  networked.  The file server to which a drive is mapped is maintain in the
  Drive Connection ID Table index into Server Name Table and Connection
  Information Table.

  Drive numbers of each search drive mapped is maintained in the Search
  Drive Vector.

  A Volume Table is maintained on the file server which tracks volumes
  mounted, along with each volumes information; volume name, total blocks,
  sectors/block, available blocks, total directory slots, available
  directory slots, and whether volume is removable.  The volume table has
  a maximum of 32 entries (0-31) under NetWare 286.  NetWare 386 increases
  this maximum.

  There are 5 calls in the FS API that are supported by functions in the
  NETTO library for volumes.  Get Volume Name - FN_VOLNAME(), Get Volume
  Number - FN_VOLNUM(), Get Volume Info With Handle - FN_VOLINFH(), Get
  Volume Info With Number - FN_VOLINFN(), and Get Volume Information -
  FN_VOLINF().

  $DIRECTORY HANDLES$

  The only directory handles available to a program are those associated
  with drives or search drives in the Drive Handle Table and Search Drive
  Vector and also any handles the program may allocate relative to the
  existing handles.  A directory handle provides an index into the Directory
  Handle Table, which points to the Directory Table and the Volume Table.
  The directory handle describes a volume and directory.  A developer can
  use directory handle calls to find handles given to drive numbers, set
  handles to other directories and to save or restore handles.

  The call Get Directory Handle - FN_GETDH() is used to find the directory
  to which a drive is mapped.  Set Directory Handle - FN_SETDH() allows
  changing the path a handle points to by giving another handle or path.
  Save Directory Handle - FN_SAVDH() and Restore Directory Handle -
  FN_RESDH() allows an application to save and restore its operating
  enviroment for batch jobs, printing or remote job handling.  Restore
  Directory Handle also returns the effective rights mask for the directory.

  File System Services API provides functions that a program can use to
  allocate its own directory handles.  These functions can be used to map
  drives.  Most users are familiar with NetWares MAP command.  With
  Allocate Permanent Directory Handle - FN_ALPERDH(), a programmer can map
  a drive that will last past the termination of the program that created
  it.  Allocate Temporary Directory Handle - FN_ALTEMDH(), allows mapping
  a drive for the duration of the session that created it or until the
  program that allocated it call the End Of Job function.  If a temporary
  directory name is the same for a permanent handle that already exists, the
  permanent handle will be lost.  Also temporary handles differ from
  permanent handles in that several temporary directory handles can be
  assigned the same drive letter but still be separately mapped to different
  directories.  Deallocate Directory Handle - FN_DEALDH() is used to remove
  a permanent or temporary directory handle and its associated drive
  mapping.
  Currently unsupported by the NETTO library are the Map Drive,
  Set Drive Path, Allocate Special Directory Handle, Is Search Drive, Get
  Search Drive Vector and Set Search Drive Vector calls.  Map Drive allows
  mapping of network drive letters to directories and can also be used to
  map and unmap search drives.  Set Drive Path allows a program to change
  the directory to which a drive is mapped or create a new drive mapping.
  The search drive vector is like DOS's PATH and consists of an array of
  15 directory handles corresponding to each of the shell's search drives.
  The Is Search Drive call can be used to determine if a drive letter is
  mapped as a search drive.  The Get Search Drive Vector call returns the
  search drive vector and Set Search Drive Vector allows setting the search
  drive vector to a array of directory handles.  Novell encourages developers
  to use Map Drive rather than Set Search Drive Vector for changing search
  Drive mappings.  Allocate Special Directory Handle is basically like
  the MAP ROOT command in NetWare.  The mapped directory cannot be changed.
  This call may not be supported in the future.

  $DIRECTORY OPERATIONS$

  Just like under DOS the File System Services provide calls in NetWare for
  performing fundamental directory operations.  The developer can create,
  delete, rename, and change directories.  There are also calls to get and
  set directory information like owner and security.  One thing to remember
  is that before making one of these calls is to ensure that the file
  server that you want to perform the action on is the current file server.
  You can set the Shell to the preferred connection by calling Set Preferred
  Connection ID - FN_SPFCID() (Connection/Workstation APIs).

  Create Directory - FN_MKDIR() creates a directory on the file server.
  Delete Directory - FN_RMDIR() deletes a directory on the file server.
  Get Current Directory - FN_GETCD() Gets current directory of a drive.
  Get Directory Path - FN_GETPATH() returns a directory path given a
  directory handle.  Rename Directory - FN_RENDIR() allows renaming a
  directory on the file server.  Scan Directory Information and Set
  Directory Information (eg, date of creation, owner, maximum rights mask)
  are not currently supported by the NETTO library.

  $TRUSTEES AND RIGHTS$

  Trustees and rights information and management functions are currently
  unsupported by the NETTO library.


 Source: N:\SRC\FSYS\XDIRECT.PRG

 Author: Gregory Anthony