Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!yale!mintaka!ai-lab!gnu.ai.mit.edu!goehring From: goehring@gnu.ai.mit.edu (Not Marc Spencer) Newsgroups: comp.unix.misc Subject: Re: Sticky bit? Message-ID: Date: 25 Mar 91 00:19:33 GMT References: <6704@navy28.UUCP> Sender: news@ai.mit.edu Reply-To: goehring@gnu.ai.mit.edu Distribution: comp Organization: Department of Tautological Pleonasms and Superfluous Redundancies Department Lines: 44 In-reply-to: gilbertd@p4.cs.man.ac.uk's message of 22 Mar 91 12:30:50 GMT In article gilbertd@p4.cs.man.ac.uk (Dave Gilbert) writes: As far as I'm aware what it does is do something like try and keep programs in memory -so that say you have 20 people using vi on a machine, it ould only hold 1 copy and also it would keep it in memory so its available immediatly Dave (I think I'm correct?) While the `sticky bit' is set on a sharable executable file, the text of that file will not be removed from the system swap area. Thus the file does not have to be fetched from the file system upon each execution. Shareable text segments are normally placed in a least-frequently-used cache after use, and thus the `sticky bit' has little effect on commonly-used text images. If the sticky bit is set on a file which has none of its execute bits set, then the kernel's buffer cache will not be used for accesses to the file. This can be used on large files (such as swap files for diskless NFS clients) so that accesses to these files will not blow everything else out of the server's buffer cache. 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. 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. -- Help stamp out vi in our lifetime! Scott Goehring goehring@gnu.ai.mit.edu On exile in Indianapolis, IN