STICKY(8) BSD System Manager's Manual STICKY(8)NAMEsticky — 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 shareable executable files and directo‐
ries. See chmod(2) or the file /usr/include/sys/stat.h for an explana‐
tion of file modes.
STICKY TEXT EXECUTABLE FILES
The sticky bit has no effect on executable files. All optimization on
whether text images remain resident in memory is handled by the kernel's
virtual memory system.
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.
BUGS
Neither open(2) nor mkdir(2) will create a file with the sticky bit set.
HISTORY
A sticky command appeared in Version 32V AT&T UNIX.
4th Berkeley Distribution June 5, 1993 4th Berkeley Distribution
