Question

如何使用python在* nix上获取文件的权限掩码，如644或755？这样做有什么功能或类吗？你能帮助我吗？非常感谢你！

Answer 1

os.stat是stat(2)系统调用接口的包装器。

>>> import os
>>> from stat import *
>>> os.stat("test.txt") # returns 10-tupel, you really want the 0th element ...
posix.stat_result(st_mode=33188, st_ino=57197013, \
    st_dev=234881026L, st_nlink=1, st_uid=501, st_gid=20, st_size=0, \
    st_atime=1300354697, st_mtime=1300354697, st_ctime=1300354697)

>>> os.stat("test.txt")[ST_MODE] # this is an int, but we like octal ...
33188

>>> oct(os.stat("test.txt")[ST_MODE])
'0100644'

从这里你将认识到典型的八进制权限。

S_IRWXU 00700   mask for file owner permissions
S_IRUSR 00400   owner has read permission
S_IWUSR 00200   owner has write permission
S_IXUSR 00100   owner has execute permission
S_IRWXG 00070   mask for group permissions
S_IRGRP 00040   group has read permission
S_IWGRP 00020   group has write permission
S_IXGRP 00010   group has execute permission
S_IRWXO 00007   mask for permissions for others (not in group)
S_IROTH 00004   others have read permission
S_IWOTH 00002   others have write permission
S_IXOTH 00001   others have execute permission

你真的只对较低的位感兴趣，所以你可以砍掉其余的：

>>> oct(os.stat("test.txt")[ST_MODE])[-3:]
'644'
>>> # or better
>>> oct(os.stat("test.txt").st_mode & 0o777)

旁注：上部确定文件类型，例如：

S_IFMT  0170000 bitmask for the file type bitfields
S_IFSOCK    0140000 socket
S_IFLNK 0120000 symbolic link
S_IFREG 0100000 regular file
S_IFBLK 0060000 block device
S_IFDIR 0040000 directory
S_IFCHR 0020000 character device
S_IFIFO 0010000 FIFO
S_ISUID 0004000 set UID bit
S_ISGID 0002000 set-group-ID bit (see below)
S_ISVTX 0001000 sticky bit (see below)

Answer 2

我认为这是获取文件权限位的最明确方式：

stat.S_IMODE(os.lstat("file").st_mode)

os.lstat函数，如果文件是符号链接，则为您提供链接本身的模式，而os.stat取消引用该链接。因此，我发现os.lstat是最常用的。

这是一个示例案例，给定常规文件＆＃34; testfile＆＃34;和符号链接到后者，＆＃34; testlink＆＃34;：

import stat
import os

print oct(stat.S_IMODE(os.lstat("testlink").st_mode))
print oct(stat.S_IMODE(os.stat("testlink").st_mode))

此脚本为我输出以下内容：

0777
0666

Answer 3

另一种方法是，如果你不想弄清楚stat的意思是使用os.access命令http://docs.python.org/library/os.html#os.access 但请阅读有关可能出现的安全问题的文档

例如，检查具有读/写权限的文件test.dat的权限

os.access("test.dat",os.R_OK)
>>> True

#Execute permissions
os.access("test.dat",os.X_OK)
>>> False

#And Combinations thereof
os.access("test.dat",os.R_OK or os.X_OK)
>>> True

os.access("test.dat",os.R_OK and os.X_OK)
>>> False

Answer 4

辛（os.stat（ '文件'）ST_MODE。）[4：

Answer 5

os模块中有很多基于文件的功能。如果您运行os.stat(filename)，您可以随时插入结果。

http://docs.python.org/library/stat.html

Answer 6

os.stat类似于c-lib stat（linux上的man 2 stat查看信息）

stats = os.stat('file.txt')
print stats.st_mode

Answer 7

os.access（path，mode）方法如果在路径上允许访问，则返回True，否则返回False。

可用模式为：

os.F_OK-测试路径是否存在。
os.R_OK-测试路径的可读性。
os.W_OK-测试路径的可写性。
os.X_OK-测试是否可以执行路径。

例如，检查文件/tmp/test.sh是否具有执行权限

ls -l /tmp/temp.sh
-rw-r--r--  1 *  *  0 Mar  2 12:05 /tmp/temp.sh

os.access('/tmp/temp.sh',os.X_OK)
False

after changing the file permission to +x 
chmod +x /tmp/temp.sh

ls -l /tmp/temp.sh
-rwxr-xr-x  1 *  *  0 Mar  2 12:05 /tmp/temp.sh

os.access('/tmp/temp.sh',os.X_OK)
True

Answer 8

如果需要，您可以使用Popen运行Bash stat命令：

正常的Bash命令：

public partial class add_thing : Form
{
    public string piccpath1 { get; set; }
    public string piccpath2 { get; set; }
    public string description { get; set; }
    public string titlee { get; set; }

    public add_thing()
    {
        InitializeComponent();
        path = piccpath1;
        path2 = piccpath2;
        description = desc;
        titlee = title;
    }

    private void button1_Click(object sender, EventArgs e)
    {
        if (openFileDialog1.ShowDialog() == System.Windows.Forms.DialogResult.OK)
        {
            string picpath = openFileDialog1.FileName;
            pictureBox1.Image = Image.FromFile(picpath);
            string[] extract = Regex.Split(picpath, "evidence");
            string pipath2 = Regex.Replace(extract[1], "evidence", "");
            piccpath1 = picpath;
            piccpath2 = pipath2; 
        }
    }

    private void button3_Click(object sender, EventArgs e)
    {
        description = richTextBox1.Text;
        titlee = textBox1.Text;
        this.DialogResult = DialogResult.OK;
        this.Close();
    }
}

然后使用Python：

jlc@server:~/NetBeansProjects/LineReverse$ stat -c '%A %a %n' revline.c
-rw-rw-r-- 664 revline.c

如果您想搜索目录，这是另一种方法：

>>> from subprocess import Popen, PIPE
>>> fname = 'revline.c'
>>> cmd = "stat -c '%A %a %n' " + fname
>>> out = Popen(cmd, shell=True, stdout=PIPE).communicate()[0].split()[1].decode()
>>> out
'664'

Answer 9

这是检查目录权限的简单方法。

import os
import stat

mode = os.stat("path_of_directory").st_mode

if not ((mode & stat.S_IWUSR):
  print ('not writable by user')

if not ((mode & stat.S_IWUSR) and (mode & stat.S_IWGRP) and (mode & stat.S_IWOTH)):
  print ('not writable by all')

标志列表如下：

S_IRWXU 00700   mask for file owner permissions
S_IRUSR 00400   owner has read permission
S_IWUSR 00200   owner has write permission
S_IXUSR 00100   owner has execute permission
S_IRWXG 00070   mask for group permissions
S_IRGRP 00040   group has read permission
S_IWGRP 00020   group has write permission
S_IXGRP 00010   group has execute permission
S_IRWXO 00007   mask for permissions for others (not in group)
S_IROTH 00004   others have read permission
S_IWOTH 00002   others have write permission
S_IXOTH 00001   others have execute permission

如何获取文件的权限掩码？

9 个答案: