table of contents
VOP_SETEXTATTR(9) | Kernel Developer's Manual | VOP_SETEXTATTR(9) |
NAME¶
VOP_SETEXTATTR
—
set named extended attribute for a vnode
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¶
AUTHORS¶
This manual page was written by Robert Watson.
December 23, 1999 | Debian |