Indicates whether the POSIX semantics for the chown(2) system call are in effect. POSIX semantics are:
A process cannot change the owner of a file unless it is running with UID 0.
A process cannot change the group ownership of a file to a group in which it is not currently a member unless it is running as UID 0.
1, indicating that POSIX semantics are used
0 = POSIX semantics not in force, 1 = POSIX semantics used
When POSIX semantics are not desired. Note that turning off POSIX semantics opens the potential for various security holes. It also opens the possibility of a user changing ownership of a file to another user and being unable to retrieve the file back without intervention from the user or the system administrator.