STICKY(7) Standards, Environments, and Macros STICKY(7)

NAME


sticky - mark files for special treatment

DESCRIPTION


The sticky bit (file mode bit 01000, see chmod(2)) is used to indicate
special treatment of certain files and directories. A directory for which
the sticky bit is set restricts deletion of files it contains. A file in
a sticky directory can only be removed or renamed by a user who has write
permission on the directory, and either owns the file, owns the
directory, has write permission on the file, or is a privileged user.
Setting the sticky bit is useful for directories such as /tmp, which must
be publicly writable but should deny users permission to arbitrarily
delete or rename the files of others.


If the sticky bit is set on a regular file and no execute bits are set,
the system's page cache will not be used to hold the file's data. This
bit is normally set on swap files of diskless clients so that accesses to
these files do not flush more valuable data from the system's cache.
Moreover, by default such files are treated as swap files, whose inode
modification times may not necessarily be correctly recorded on permanent
storage.


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

SEE ALSO


chmod(1), chmod(2), chown(2), mkdir(2), rename(2), unlink(2)

BUGS


The mkdir(2) function will not create a directory with the sticky bit
set.

illumos August 1, 2002 STICKY(7)