zoukankan      html  css  js  c++  java
  • Linux file permission partial

    Most versions of Linux have two types of user accounts: standard and root.

    The root user can access and /or delete whatever files it wants. 

    It can configure hardware,change settings, and so on.

    Ububntu is different in that it doesn't allow login as the root user. Instead, it allows certain users, 

    including the one created during installation, to adopt temporarily root-like powers. 
    This way of working is referred to as sudo, which is short for superuser do.

    The file permissions part of a file listing can be broken down into four separate parts.

    Type of file:  A standard data file is indicated with a dash(-). Most files on your system fall

    into this category. 

    A d shows that the entry is not a file but a directory.

    User permissions: Read(r),Write(w),Execute(x)

    Group permissions:

    Everyone else's permissions: other users in other groups.

    File Type Codes

    Code File type

    -  Standard file

    d  Standard directory

    l   Symbolic link(a shortcut to another file)

    p    Named pipe(a file that act as a conduit for data between two programs)

    s  Socket

    c  Character device( a hardware device driver, usually found in /dev)

    b  Block Device (a hardware device driver, usually found in /dev)

    Change the permissions:

    chmod a+rw filename   : (chmod +rw filename do the same thing, a is for all the user.)

    chmod u+rw    Change permissions just for the owner( u is for user, which is the same as owner).

    chmod u+x myprogram

    Numeric file permissions

    r for reader,w for write, x for execute. This is know as symbolic notation, and its goal is to make file permissions intuitive and easy for the user to understand. However, Unix and Linux file permissions are traditionally expressed as octal notation. 

    r (Reader):4 , w(Write):2, x(Execute):1 .

    so (rwx) has a value 7(4+2+1)

    chmod 644 myfile.txt  means -rw-r--r-- for myfile.txt

    -----------------------------------------------------------------------

    With this information in hand, you’re now ready to mount the disk. For a FAT32disk (that is, one from an older Windows installation, such as 95, 98, Me, or olderWindows XP setups), type the following:
    sudo mount -t vfat -o umask=000 /dev/sdb1 /media/newdisk
    . For an NTFS disk, type the following:
    sudo mount -t ntfs-3g /dev/sdb1 /media/newdisk

    Removing a Mounted Systemsudo umount /media/newdisk
    File Searches

    find /home/keir -name "myfile"

  • 相关阅读:
    Live2d Test Env
    Live2d Test Env
    Live2d Test Env
    图神经网络入门
    CommandLineRunner 可能会导致你的应用宕机停止,我劝你耗子尾汁
    不使用 MQ 如何实现 pub/sub 场景?
    为什么 @Value 可以获取配置中心的值?
    vite + ts 快速搭建 vue3 项目 以及介绍相关特性
    给 Mac 添加右键菜单「使用 VSCode 打开」
    【Python】连接常用数据库
  • 原文地址:https://www.cnblogs.com/wucg/p/1853095.html
Copyright © 2011-2022 走看看