vop_listextattr(9)

NAME

VOP_LISTEXTATTR - retrieve a list of named extended at

tribute from a
vnode

SYNOPSIS

#include <sys/param.h>
#include <sys/vnode.h>
#include <sys/extattr.h>
int
VOP_LISTEXTATTR(struct  vnode *vp, int attrnamespace, struct
uio *uio,
        size_t *size,  struct  ucred  *cred,  struct  thread
*td);

DESCRIPTION

This vnode call may be used to retrieve a list of named ex

tended
attributes from a specified namespace on a file or directo

ry.

Its arguments are:

vp The vnode of the file or directory.

attrnamespace Integer constant indicating which extend

ed attribute

namespace the attribute name is present

in.

uio The location of the data to be read. The

resulting

data will be a list of attribute names.

Each list
entry consists of a single byte contain

ing the length
of the attribute name, followed by the

attribute name.
The attribute name is not terminated by

ASCII NUL.

size If not NULL, on return it will contain

the number of

bytes required to read the list. In most

cases uio
will be NULL when size is not, and vise

versa.

cred The user credentials to use in authoriz

ing the

request.

td The thread requesting the extended at

tribute.

The cred pointer may be NULL to indicate that access control

checks are
not to be performed, if possible. This cred setting might

be used to
allow the kernel to authorize extended attribute retrieval

that the
active process might not be permitted to do.

Extended attribute semantics may vary by file system imple

menting the
call. More information on extended attributes may be found

in
extattr(9).

LOCKS

The vnode will be locked on entry and should remain locked

on return.

RETURN VALUES

On success, zero will be returned, and the uio structure

will be updated
to reflect the list read. Otherwise, an appropriate error

code is
returned.

ERRORS

[EACCES] The caller does not have the appropriate

privilege.

[ENXIO] The request was not valid in this file

system for the

specified vnode and attribute name.

[ENOMEM] Sufficient memory is not available to

fulfill the

request.

[EFAULT] The uio structure refers to an invalid

userspace

address.

[EINVAL] The namespace or uio argument is invalid.

[EOPNOTSUPP] The file system does not support

VOP_LISTEXTATTR

SEE ALSO

extattr(9), vnode(9), VOP_GETEXTATTR(9), VOP_SETEXTATTR(9)

BSD August 19, 2005

BSD