VOP_LISTEXTATTR(9) BSD Kernel Developer's Manual VOP_LISTEXTATTR(9)NAMEVOP_LISTEXTATTR — retrieve a list of named extended attribute 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 extended
attributes from a specified namespace on a file or directory.
Its arguments are:
vp The vnode of the file or directory.
attrnamespace Integer constant indicating which extended 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 con‐
sists of a single byte containing 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 authorizing the request.
td The thread requesting the extended attribute.
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 implementing 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 ALSOextattr(9), vnode(9), VOP_GETEXTATTR(9), VOP_SETEXTATTR(9)BSD August 19, 2005 BSD
