File Attribute

 The file attribute is a 1-byte bit-flag associated with each file, found
 in the file's directory entry and used in several DOS functions.

║   │advshr║
╙─┴─┴╥┴╥┴╥┴╥┴╥┴╥╜ bit mask
     ║ ║ ║ ║ ║ ╚═► 0:  01H 1=Read-only (file can't be written/deleted)
     ║ ║ ║ ║ ╚═══► 1:  02H 1=Hidden
     ║ ║ ║ ╚═════► 2:  04H 1=System
     ║ ║ ╚═══════► 3:  08H 1=Volume label entry
     ║ ╚═════════► 4:  10H 1=subDirectory entry
     ╚═══════════► 5:  20H Archive bit. 1=file has NOT been backed up

                     Some Commonly-Seen File Attributes
 Attr  Meaning
 ▀▀▀▀  ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀
   0   a normal file
   3   read-only, hidden, and system (used in system files)
   8   the volume label entry (should be found only in the root directory)
  10H  a directory
  20H  a normal file which has not been backed up by BACKUP or XCOPY
 ▀▀▀▀  ▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀▀

 DOS Fn 11H and 4eH directory searches are inclusive.  You can set one or
 more  of the file attribute bits for Hidden, System, Directory, and
 Archive if you  want to search for files with one or more of these
 attributes.  When a bit is clear, files that have that attribute will NOT
 be found.

 For instance, if you want to locate directory entries only, you can use an
 attribute of 10H to obtain a set of all files including directories, then
 ignore all the entries that are not directories (having bit 4=0).

 If you specify an attribute with the Volume bit, the search will be
 exclusive, returning only the entry of the volume label (if any).

 DOS Fn 43H (set file attribute) will let you set or clear the Read-only,
 Hidden, System, and Archive bits.  You cannot alter the Directory
 attribute bit, but you can add or remove other bits of the directory's
 attribute by specifying an attribute having all the desired bits for the
 directory EXCEPT bit 4.

See Also: Directory and File Functions
          Data Structures