Unknown option: "-7" Unix manual page for sticky. (host=minya system=Darwin)
STICKY(7)            BSD Miscellaneous Information Manual            STICKY(7)

NAME
     sticky -- sticky text and append-only directories

DESCRIPTION
     A special file mode, called the sticky bit (mode S_ISVTX), is used to
     indicate special treatment for directories.  It is ignored for regular
     files.  See chmod(2) or the file <sys/stat.h> for an explanation of file
     modes.

STICKY DIRECTORIES
     A directory whose `sticky bit' is set becomes an append-only directory,
     or, more accurately, a directory in which the deletion of files is
     restricted.  A file in a sticky directory may only be removed or renamed
     by a user if the user has write permission for the directory and the user
     is the owner of the file, the owner of the directory, or the super-user.
     This feature is usefully applied to directories such as /tmp which must
     be publicly writable but should deny users the license to arbitrarily
     delete or rename each others' files.

     Any user may create a sticky directory.  See chmod(1) for details about
     modifying file modes.

HISTORY
     A sticky command appeared in Version 32V AT&T UNIX.

BUGS
     Neither open(2) nor mkdir(2) will create a file with the sticky bit set.

BSD                              June 5, 1993                              BSD