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.\" 28.Dd December 23, 1999 29.Dt VOP_GETEXTATTR 9 30.Os 31.Sh NAME 32.Nm VOP_GETEXTATTR 33.Nd retrieve named extended attribute from a vnode 34.Sh SYNOPSIS 35.In sys/param.h 36.In sys/vnode.h 37.In sys/extattr.h 38.Ft int 39.Fn VOP_GETEXTATTR "struct vnode *vp" "char *name" "struct uio *uio" "struct ucred *cred" "struct proc *p" 40.Sh DESCRIPTION 41This vnode call may be used to retrieve a specific named extended attribute 42from a file or directory. 43.Pp 44Its arguments are: 45.Bl -tag -width type 46.It Fa vp 47the vnode of the file or directory 48.It Fa name 49pointer to a null-terminated character string containing the attribute name 50.It Fa uio 51the location of the data to be read or written 52.It Fa cred 53the user credentials to use in authorizing the request 54.It Fa p 55the process requesting the extended attribute 56.El 57.Pp 58The 59.Fa cred 60pointer may be 61.Dv NULL 62to indicate that access control checks are not to be performed, if possible. 63This 64.Fa cred 65setting might be used to allow the kernel to authorize extended attribute 66retrieval that the active process might not be permitted to do. 67.Pp 68Extended attribute semantics may vary by file system implementing the call. 69More information on extended attributes may be found in 70.Xr extattr 9 . 71.Sh LOCKS 72No locks are required to call this vnode method, and any locks held on 73entry will be held on exit. 74.Sh RETURN VALUES 75On success, zero will be returned, and the uio structure will be updated to 76reflect data read. Otherwise, an appropriate error code is returned. 77.Sh ERRORS 78.Bl -tag -width Er 79.It Bq Er ENOENT 80The attribute name is not defined for this vnode 81.It Bq Er EACCES 82Permission denied 83.It Bq Er ENXIO 84The request was not valid in this file system for the specified vnode and 85attribute name. 86.It Bq Er ENOMEM 87Insufficient memory available to fulfill request 88.It Bq Er EFAULT 89The uio structure refers to an invalid userspace address. 90.It Bq Er EINVAL 91The 92.Fa name 93or 94.Fa uio 95argument is invalid. 96.It Bq Er EOPNOTSUPP 97The file system does not support 98.Fn VOP_GETEXTATTR 99.El 100.Sh SEE ALSO 101.Xr extattr 9 , 102.Xr vnode 9 , 103.Xr VOP_SETEXTATTR 9 104