1.\"- 2.\" Copyright (c) 1999 Robert N. M. Watson 3.\" All rights reserved. 4.\" 5.\" Redistribution and use in source and binary forms, with or without 6.\" modification, are permitted provided that the following conditions 7.\" are met: 8.\" 1. Redistributions of source code must retain the above copyright 9.\" notice, this list of conditions and the following disclaimer. 10.\" 2. Redistributions in binary form must reproduce the above copyright 11.\" notice, this list of conditions and the following disclaimer in the 12.\" documentation and/or other materials provided with the distribution. 13.\" 14.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 15.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 16.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 17.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 18.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 19.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 20.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 21.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 22.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 23.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 24.\" SUCH DAMAGE. 25.\" 26.\" $FreeBSD: src/share/man/man9/VOP_GETEXTATTR.9,v 1.1.2.3 2001/12/17 11:30:18 ru Exp $ 27.\" $DragonFly: src/share/man/man9/VOP_GETEXTATTR.9,v 1.2 2003/06/17 04:37:01 dillon Exp $ 28.\" 29.Dd December 23, 1999 30.Os 31.Dt VOP_GETEXTATTR 9 32.Sh NAME 33.Nm VOP_GETEXTATTR 34.Nd retrieve named extended attribute from a vnode 35.Sh SYNOPSIS 36.In sys/param.h 37.In sys/vnode.h 38.In sys/extattr.h 39.Ft int 40.Fn VOP_GETEXTATTR "struct vnode *vp" "char *name" "struct uio *uio" "struct ucred *cred" "struct proc *p" 41.Sh DESCRIPTION 42This vnode call may be used to retrieve a specific named extended attribute 43from a file or directory. 44.Pp 45Its arguments are: 46.Bl -tag -width type 47.It Fa vp 48the vnode of the file or directory 49.It Fa name 50pointer to a null-terminated character string containing the attribute name 51.It Fa uio 52the location of the data to be read or written 53.It Fa cred 54the user credentials to use in authorizing the request 55.It Fa p 56the process requesting the extended attribute 57.El 58.Pp 59The 60.Fa cred 61pointer may be 62.Dv NULL 63to indicate that access control checks are not to be performed, if possible. 64This 65.Fa cred 66setting might be used to allow the kernel to authorize extended attribute 67retrieval that the active process might not be permitted to do. 68.Pp 69Extended attribute semantics may vary by file system implementing the call. 70More information on extended attributes may be found in 71.Xr extattr 9 . 72.Sh LOCKS 73No locks are required to call this vnode method, and any locks held on 74entry will be held on exit. 75.Sh RETURN VALUES 76On success, zero will be returned, and the uio structure will be updated to 77reflect data read. Otherwise, an appropriate error code is returned. 78.Sh ERRORS 79.Bl -tag -width Er 80.It Bq Er ENOENT 81The attribute name is not defined for this vnode 82.It Bq Er EACCES 83Permission denied 84.It Bq Er ENXIO 85The request was not valid in this file system for the specified vnode and 86attribute name. 87.It Bq Er ENOMEM 88Insufficient memory available to fulfill request 89.It Bq Er EFAULT 90The uio structure refers to an invalid userspace address. 91.It Bq Er EINVAL 92The 93.Fa name 94or 95.Fa uio 96argument is invalid. 97.It Bq Er EOPNOTSUPP 98The file system does not support 99.Fn VOP_GETEXTATTR 100.El 101.Sh SEE ALSO 102.Xr extattr 9 , 103.Xr vnode 9 , 104.Xr VOP_SETEXTATTR 9 105