xattr_set
(PECL xattr >= 0.9.0)
xattr_set — Set an extended attribute
说明
xattr_set
( string
$filename
, string $name
, string $value
[, int $flags
= 0
] ) : boolThis function sets the value of an extended attribute of a file.
扩展的属性有两种 不同的命名空间:user
和 root。user 命名空间对所有用户均有效,而 root
命名空间仅对拥有 root 权限的用户有效。
xattr 默认在 user 命名空间上操作,但可使用
flags
参数进行更改。
参数
-
filename
-
The file in which we set the attribute.
-
name
-
The name of the extended attribute. This attribute will be created if it doesn't exist or replaced otherwise. You can change this behaviour by using the
flags
parameter. -
value
-
The value of the attribute.
-
flags
-
Supported xattr flags XATTR_CREATE
Function will fail if extended attribute already exists. XATTR_REPLACE
Function will fail if extended attribute doesn't exist. XATTR_DONTFOLLOW
Do not follow the symbolic link but operate on symbolic link itself. XATTR_ROOT
Set attribute in root (trusted) namespace. Requires root privileges.
返回值
成功时返回 TRUE
, 或者在失败时返回 FALSE
。
范例
Example #1 Sets extended attributes on .wav file
<?php
$file = 'my_favourite_song.wav';
xattr_set($file, 'Artist', 'Someone');
xattr_set($file, 'My ranking', 'Good');
xattr_set($file, 'Listen count', '34');
/* ... other code ... */
printf("You've played this song %d times", xattr_get($file, 'Listen count'));
?>