example in form of a Kerberos realm name an Active Directory domain name the name of an operating-system vendor (for distribution-specific allocations) the name of a computer (for device-specific allocations) But in practice many existing implementations only allow setting the NFSv4 domain to a fixed value, thereby rendering it useless. See also setuid Sticky bit Group identifier Process identifier File system permissions Open (system call) Mount (Unix) FAT access rights Security Identifier (SID) – the Windows NT equivalent References Unix Unix file system technology