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diff --git a/share/man/man9/extattr.9 b/share/man/man9/extattr.9 new file mode 100644 index 000000000000..9c74a60bf9bc --- /dev/null +++ b/share/man/man9/extattr.9 @@ -0,0 +1,96 @@ +.\"- +.\" Copyright (c) 1999, 2000, 2001, 2003 Robert N. M. Watson +.\" 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. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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. +.\" +.\" $FreeBSD$ +.\" +.Dd December 23, 1999 +.Os +.Dt EXTATTR 9 +.Sh NAME +.Nm extattr +.Nd virtual file system named extended attributes +.Sh SYNOPSIS +.In sys/param.h +.In sys/vnode.h +.In sys/extattr.h +.Sh DESCRIPTION +Named extended attributes allow additional meta-data to be associated +with vnodes representing files and directories. +The semantics of this additional data is that of a "name=value" pair, where +a name may be defined or undefined, and if defined, associated with zero or +more bytes of arbitrary binary data. +Extended attribute names exist within a set of namespaces; each operation +on an extended attribute is required to provide the namespace to which to +operation refers. +If the same name is present in multiple namespaces, the extended attributes +associated with the names are stored and manipulated independently. +The following two namespaces are defined universally, although individual +file systems may implement additional namespaces, or not implement +these namespaces: +.Dv EXTATTR_NAMESPACE_USER , +.Dv EXTATTR_NAMESPACE_SYSTEM . +The semantics of these attributes are intended to be as follows: user +attribute data is protected according the normal discretionary +and mandatory protections associated with the data in the file or +directory; system attribute data is protected such that appropriate +privilege is required to directly access or manipulate these attributes. +.Pp +Reads of extended attribute data may return specific contiguous regions of +the meta-data, in the style of +.Xr VOP_READ 9 , +but writes will replace the entire current "value" associated with +a given name. +As there are a plethora of file systems with differing extended attributes, +availability and functionality of these functions may be limited, and they +should be used with awareness of the underlying semantics of the supporting +file system. +Authorization schemes for extended attribute data may also vary by file +system, as well as maximum attribute size, and whether or not any or +specific new attributes may be defined. +.Pp +Extended attributes are named using a null-terminated character string. +Depending on underlying file system semantics, this name may or may not be +case-sensitive. +Appropriate vnode extended attribute calls are: +.Xr VOP_GETEXTATTR 9 , +.Xr VOP_LISTEXTATTR 9 , +and +.Xr VOP_SETEXTATTR 9 . +.Sh SEE ALSO +.Xr VFS 9 , +.Xr VFS_EXTATTRCTL 9 , +.Xr VOP_GETEXTATTR 9 , +.Xr VOP_LISTEXTATTR 9 , +.Xr VOP_SETEXTATTR 9 +.Sh AUTHORS +This manual page was written by +.An Robert Watson . +.Sh BUGS +In addition, the interface does not provide a mechanism to retrieve +the current set of available attributes; it has been suggested that +providing a +.Dv NULL +attribute name should cause a list of defined attributes for the passed file +or directory, but this is not currently implemented. |