stat（）和＆符号运算符

Question

我一直在研究在文件系统上运行的WordPress源代码，当我点击这几行并且我真的不太清楚他们做了什么？

$stat = stat( dirname( $new_file ));
$perms = $stat['mode'] & 0000666;
@ chmod( $new_file, $perms );

Answer 1

该代码使用按位运算来确保文件的权限不高于666。 要打破它：

// Retrieves the file details, including current file permissions.
$stat = stat( dirname( $new_file )); 

// The file permissions are and-ed with the octal value 0000666 to make
// sure that the file mode is no higher than 666. In other words, it locks
// the file down, making sure that current permissions are no higher than 666,
// or owner, group and world read/write.
$perms = $stat['mode'] & 0000666; 

// Finally, the new permissions are set back on the file
@chmod( $new_file, $perms );

Answer 2

它改变了允许在目录中写入的权限..我想。查看stat()和chmod()。

Answer 3

0666是unix rwxrwxrwx权限的八进制表示法，因此我假设$stat['mode']返回该文件夹的权限。然后，他们与0666掩码进行按位AND运算，以检查您是否至少 读取/写入/执行自己，组和其他人的权限。