为什么PHP无法创建具有777权限的目录? [英] Why can't PHP create a directory with 777 permissions?

问题描述

我正在尝试通过以下命令使用PHP在服务器上创建目录:

I'm trying to create a directory on my server using PHP with the command:

mkdir("test", 0777);

但是它不提供全部权限，仅授予以下权限:

But it doesn't give full permissions, only these:

rwxr-xr-x

推荐答案

该模式已由您当前的umask修改，本例中为022.

The mode is modified by your current umask, which is 022 in this case.

umask的工作方式是减法.您获得对mkdir的初始许可权，并减去umask以获得 actual 许可权:

The way the umask works is a subtractive one. You take the initial permission given to mkdir and subtract the umask to get the actual permission:

  0777
- 0022
======
  0755 = rwxr-xr-x.

如果您不希望发生这种情况，则需要将umask临时设置为零，以使其无效.您可以使用以下代码段进行此操作:

If you don't want this to happen, you need to set your umask temporarily to zero so it has no effect. You can do this with the following snippet:

$oldmask = umask(0);
mkdir("test", 0777);
umask($oldmask);

第一行将umask更改为零，同时将前一个存储到$oldmask中.第二行使用所需的权限和(现在不相关的)umask创建目录.第三行将umask恢复为原始状态.

The first line changes the umask to zero while storing the previous one into $oldmask. The second line makes the directory using the desired permissions and (now irrelevant) umask. The third line restores the umask to what it was originally.

有关 umask 和

See the PHP doco for umask and mkdir for more details.

这篇关于为什么PHP无法创建具有777权限的目录?的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！