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Manual Pages  — VOP_SETEXTATTR

NAME

VOP_SETEXTATTR – set named extended attribute for a vnode

CONTENTS

SYNOPSIS

#include <sys/param.h>
#include <sys/vnode.h>
#include <sys/extattr.h>

int
VOP_SETEXTATTR(struct vnode *vp, int attrnamespace, const char *name, struct uio *uio, struct ucred *cred, struct thread *td);

DESCRIPTION

This vnode call may be used to set specific named extended attribute for 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.
name
  Pointer to a null-terminated character string containing the attribute name.
uio
  The location of the data to be read or written.
cred
  The user credentials to use in authorizing the request.
td
  The thread setting the extended attribute.

The uio structure is used in a manner similar to the argument of the same name in VOP_WRITE(9). However, as extended attributes provide a strict "name=value" semantic, non-zero offsets will be rejected.

The uio pointer may be NULL to indicate that the specified extended attribute should be deleted.

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 changes that the active process might not be permitted to make.

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

If the extended attribute is successfully set, then zero is returned. 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]
  Insufficient memory available to fulfill the request.
[EFAULT]
  The uio structure refers to an invalid userspace address.
[EINVAL]
  The name, namespace, or uio argument is invalid.
[EOPNOTSUPP]
  The file system does not support VOP_SETEXTATTR().
[ENOSPC]
  The file system is out of space.
[EROFS]
  The file system is read-only.

SEE ALSO

extattr(9), vnode(9), VOP_GETEXTATTR(9), VOP_LISTEXTATTR(9)

AUTHORS

This manual page was written by Robert Watson.

VOP_SETEXTATTR (9) December 23, 1999

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