xattr_set
(PECL xattr:0.9-1.0)
xattr_set — Set an extended attribute
说明
bool xattr_set
( string $filename
, string $name
, string $value
[, int $flags
] )
This function sets the value of an extended attribute of a file.
扩展的属性有两个不同的名字空间：user 和 root 名字空间。user 名字空间对所有用户均有效，而 root 名字空间仅对拥有 root 权限的用户有效。xattr 默认在 user 名字空间上进行操作，但是可以使用 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
如果成功则返回 TRUE，失败则返回 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'));
?>
