(PHP 4, PHP 5)
fileperms — 取得文件的权限
$filename
)取得文件的权限。
filename
文件的路径。
以数字模式返回文件的访问权限。
Returns the file's permissions as a numeric mode.
Lower bits of this mode
are the same as the permissions expected by chmod(),
however on most platforms the return value will also include information on
the type of file given as filename. The examples
below demonstrate how to test the return value for specific permissions and
file types on POSIX systems, including Linux and Mac OS X.
For local files, the specific return value is that of the st_mode member of the structure returned by the C library's stat() function. Exactly which bits are set can vary from platform to platform, and looking up your specific platform's documentation is recommended if parsing the non-permission bits of the return value is required.
Example #1 以八进制的形式显示文件的权限
<?php
echo substr(sprintf('%o', fileperms('/tmp')), -4);
echo substr(sprintf('%o', fileperms('/etc/passwd')), -4);
?>
以上例程会输出：
1777 0644
Example #2 输出全部权限
<?php
$perms = fileperms('/etc/passwd');
if (($perms & 0xC000) == 0xC000) {
// Socket
$info = 's';
} elseif (($perms & 0xA000) == 0xA000) {
// Symbolic Link
$info = 'l';
} elseif (($perms & 0x8000) == 0x8000) {
// Regular
$info = '-';
} elseif (($perms & 0x6000) == 0x6000) {
// Block special
$info = 'b';
} elseif (($perms & 0x4000) == 0x4000) {
// Directory
$info = 'd';
} elseif (($perms & 0x2000) == 0x2000) {
// Character special
$info = 'c';
} elseif (($perms & 0x1000) == 0x1000) {
// FIFO pipe
$info = 'p';
} else {
// Unknown
$info = 'u';
}
// Owner
$info .= (($perms & 0x0100) ? 'r' : '-');
$info .= (($perms & 0x0080) ? 'w' : '-');
$info .= (($perms & 0x0040) ?
(($perms & 0x0800) ? 's' : 'x' ) :
(($perms & 0x0800) ? 'S' : '-'));
// Group
$info .= (($perms & 0x0020) ? 'r' : '-');
$info .= (($perms & 0x0010) ? 'w' : '-');
$info .= (($perms & 0x0008) ?
(($perms & 0x0400) ? 's' : 'x' ) :
(($perms & 0x0400) ? 'S' : '-'));
// World
$info .= (($perms & 0x0004) ? 'r' : '-');
$info .= (($perms & 0x0002) ? 'w' : '-');
$info .= (($perms & 0x0001) ?
(($perms & 0x0200) ? 't' : 'x' ) :
(($perms & 0x0200) ? 'T' : '-'));
echo $info;
?>
以上例程会输出：
-rw-r--r--
失败时抛出E_WARNING警告.
Note: 此函数的结果会被缓存。参见 clearstatcache() 以获得更多细节。
自 PHP 5.0.0 起, 此函数也用于某些 URL 包装器。请参见 支持的协议和封装协议以获得支持 stat() 系列函数功能的包装器列表。