.\" $NetBSD: sticky.8,v 1.3 1994/11/30 19:36:27 jtc Exp $ .\" .\" Copyright (c) 1980, 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)sticky.8 8.1 (Berkeley) 6/5/93 .\" .Dd June 5, 1993 .Dt STICKY 8 .Os BSD 4 .Sh NAME .Nm sticky .Nd sticky text and append-only directories .Sh DESCRIPTION A special file mode, called the .Em sticky bit (mode S_ISVTX), is used to indicate special treatment for shareable executable files and directories. See .Xr chmod 2 or the file .Pa /usr/include/sys/stat.h for an explanation of file modes. .Sh 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. .Sh 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 .Pa /tmp which must be publicly writable but should deny users the license to arbitrarily delete or rename each others' files. .Pp Any user may create a sticky directory. See .Xr chmod 1 for details about modifying file modes. .Sh BUGS Neither .Xr open 2 nor .Xr mkdir 2 will create a file with the sticky bit set. .Sh HISTORY A .Nm command appeared in Version 32V AT&T UNIX.