1. 挂載 ntfs：

确定已经安装了rpmforge软件库的源。在线安装使用 yum install 命令 含有 rpmforge源。

yum install fuse ntfs-3g -y

安装后， 打开 我的电脑  打开对应硬盘 （包含移动硬盘 、U盘）：

（1）若是电脑与Linux分区所在盘则提示需要root授权，输入密码即可访问。

（2）若是 移动硬盘、U盘， 则直接可打开。

2.   pipe ：

管道：名词表示两个进程的通信通道

动词表示通道机制

表示： cat hard_link_to_list | grep a
cat查看 hard_link_to_list文件 ， 利用管道 | 输出到 Terminal ， 通过 grep 筛选

表示： cat hard_link_to_list | more
文件大，管道输出到more

3.Permission

[alex@example.com photos]$ ls –l
total 2
drwxrwxrwx 2 alex alex 4096 oct 31 11:35 Holidays in France
-rw-rw-r-- 1 alex alex    8 oct 31 09:21 photo2.jpg

File Permision：

First character: File type (-: fle, d: directory, l: link; other types exist)
Second to fourth characters: Read, write, and execute permissions for   the owner
Fifth to seventh characters: Read, write, and execute permissions for   the group
Eighth to tenth characters: Read, write, and execute permissions for   other users

Permissions on a directory differ from regular fle permissions:
The x bit specifes whether or not the folder can be entered (such as using cd)
The r bit allows the directory content to be listed (such as using ls)
The w bit specifes whether or not new fles can be written in the folder   
(and existing fles moved to the folder)

4. Linux  Directory Infro

Path Description
/ The root directory: Not to be confused with /root. No fles are usually  placed at the root, although nothing really prevents you from doing so.
/bin Binaries: Common executable binaries and scripts available for all users of the  system. This is where essential programs such as ls, cp, or mv are found.
/boot Boot: Critical fles used at system boot time.
/dev Devices: Device and special fles, more information in the next section.
/etc Et cetera: System-wide confguration fles for services and applications. You  will often need to browse this directory, for example, when you will need to  edit the Nginx server settings and virtual hosts.
/home Home directories: This directory contains home directories for all users on  the system except the root user. In the examples we studied before we used  
/home/alex, the home directory for the alex user.
/lib Libraries: System-wide shared libraries and kernel modules, required by  binaries found in the /bin and /sbin folders.
/media Removable media: A directory that allows you to easily access removable  media using mount points for devices such as CD-ROMs, USB devices,   and so on.
/mnt Temporarily mounted flesystems: This directory is a suitable placeholder in  case the administrator wishes to mount a flesystem on a temporary basis.
/opt Optional software packages: In theory, this directory should host application  fles and add-on packages that do not come with the default operating system  
installation. In practice, it is hardly ever used.
/proc Kernel and process information virtual flesystem: This directory provides  access to a virtual flesystem containing a variety of statistics and details about  
all running processes.
/root Root user home directory: The root user, also known as Superuser, does not  have its home directory stored in the same folder as regular users (/home).  
Instead, its personal fles are stored in the /root. directory. The slash-root  (/root) directory is not to be confused with the root directory (/).
/sbin System binaries: Utilities dedicated to system administration, thus generally  accessed by the root user only. Programs such as ifconfg, halt, service, and  
many others can be found here.
/srv Service data: A placeholder for data coming from services hosted on the  system. Like many others, this directory is rarely used.
/tmp Temporary fles: Files that do not need to be conserved beyond program  execution should be stored here. Many operating systems actually clear the  
contents of this directory on reboot.