1.\"- 2.\" Copyright (c) 2003 Network Associates Technology, Inc. 3.\" All rights reserved. 4.\" 5.\" This software was developed for the FreeBSD Project in part by Network 6.\" Associates Laboratories, the Security Research Division of Network 7.\" Associates, Inc. under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), 8.\" as part of the DARPA CHATS research program. 9.\" 10.\" Redistribution and use in source and binary forms, with or without 11.\" modification, are permitted provided that the following conditions 12.\" are met: 13.\" 1. Redistributions of source code must retain the above copyright 14.\" notice, this list of conditions and the following disclaimer. 15.\" 2. Redistributions in binary form must reproduce the above copyright 16.\" notice, this list of conditions and the following disclaimer in the 17.\" documentation and/or other materials provided with the distribution. 18.\" 19.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 20.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 23.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29.\" SUCH DAMAGE. 30.\" 31.\" $FreeBSD$ 32.\" 33.Dd August 19, 2005 34.Os 35.Dt VOP_LISTEXTATTR 9 36.Sh NAME 37.Nm VOP_LISTEXTATTR 38.Nd retrieve a list of named extended attribute from a vnode 39.Sh SYNOPSIS 40.In sys/param.h 41.In sys/vnode.h 42.In sys/extattr.h 43.Ft int 44.Fo VOP_LISTEXTATTR 45.Fa "struct vnode *vp" 46.Fa "int attrnamespace" 47.Fa "struct uio *uio" 48.Fa "size_t *size" 49.Fa "struct ucred *cred" 50.Fa "struct thread *td" 51.Fc 52.Sh DESCRIPTION 53This vnode call may be used to retrieve a list of named extended attributes 54from a specified namespace on a file or directory. 55.Pp 56Its arguments are: 57.Bl -tag -width ".Fa attrnamespace" 58.It Fa vp 59The vnode of the file or directory. 60.It Fa attrnamespace 61Integer constant indicating which extended attribute namespace the attribute 62name is present in. 63.It Fa uio 64The location of the data to be read. 65The resulting data will be a list of attribute names. 66Each list entry consists of a single byte containing the length of 67the attribute name, followed by the attribute name. 68The attribute name is not terminated by 69.Tn ASCII 70.Dv NUL . 71.It Fa size 72If not 73.Dv NULL , 74on return it will contain the number of bytes required to read the list. 75In most cases 76.Fa uio 77will be 78.Dv NULL 79when 80.Fa size 81is not, and vise versa. 82.It Fa cred 83The user credentials to use in authorizing the request. 84.It Fa td 85The thread requesting the extended attribute. 86.El 87.Pp 88The 89.Fa cred 90pointer may be 91.Dv NULL 92to indicate that access control checks are not to be performed, if possible. 93This 94.Fa cred 95setting might be used to allow the kernel to authorize extended attribute 96retrieval that the active process might not be permitted to do. 97.Pp 98Extended attribute semantics may vary by file system implementing the call. 99More information on extended attributes may be found in 100.Xr extattr 9 . 101.Sh LOCKS 102The vnode will be locked on entry and should remain locked on return. 103.Sh RETURN VALUES 104On success, zero will be returned, and the 105.Fa uio 106structure will be updated to 107reflect the list read. 108Otherwise, an appropriate error code is returned. 109.Sh ERRORS 110.Bl -tag -width Er 111.It Bq Er EACCES 112The caller does not have the appropriate privilege. 113.It Bq Er ENXIO 114The request was not valid in this file system for the specified vnode and 115attribute name. 116.It Bq Er ENOMEM 117Sufficient memory is not available to fulfill the request. 118.It Bq Er EFAULT 119The 120.Fa uio 121structure refers to an invalid userspace address. 122.It Bq Er EINVAL 123The 124.Fa namespace 125or 126.Fa uio 127argument is invalid. 128.It Bq Er EOPNOTSUPP 129The file system does not support 130.Fn VOP_LISTEXTATTR . 131.El 132.Sh SEE ALSO 133.Xr extattr 9 , 134.Xr vnode 9 , 135.Xr VOP_GETEXTATTR 9 , 136.Xr VOP_SETEXTATTR 9 137