Linux软连接硬链接

 

 

• 软硬连接命令比较

1 create a hard link,

ln file link

2 create a symbolic link where “item” is either a file or a directory

ln -s item link

• 硬链接例子

创建硬连接之前

/var/root/document # ls -liF                                                    

total 4                                                                         

    276 drwxr-xr-x    2 root     root            40 Nov 27 22:49 dir1/          

    277 drwxr-xr-x    2 root     root            40 Nov 27 22:49 dir2/          

    275 -rw-r--r--    1 root     root             4 Nov 27 22:49 fun.txt 

 

 

/var/root/document # ln fun fun-hard                                            

/var/root/document # ln fun dir1/fun-hard                                       

/var/root/document # ln fun dir2/fun-hard                                       

/var/root/document # ls -li                                                     

total 8                                                                         

    276 drwxr-xr-x    2 root     root            60 Nov 27 22:51 dir1           

    277 drwxr-xr-x    2 root     root            60 Nov 27 22:52 dir2           

    275 -rw-r--r--    4 root     root             4 Nov 27 22:49 fun            

    275 -rw-r--r--    4 root     root             4 Nov 27 22:49 fun-hard       

/var/root/document # ls -li dir1/ dir2/                                         

dir1/:                                                                          

total 4                                                                         

    275 -rw-r--r--    4 root     root             4 Nov 27 22:49 fun-hard       

dir2/:                                                                          

total 4                                                                         

    275 -rw-r--r--    4 root     root             4 Nov 27 22:49 fun-hard    

both fun and fun-hard share the same inode number<275>, which confirms they are the same file.

4 which is the number of hard links that now exist for the file.

• 软连接例子

 

•  软硬连接显示比较

硬链接与普通文件无区别

软连接带符号指向源文件

• 实质

1软连接相当于win OS的快捷方式

2硬链接相当于文件内容一样但是inode各不相同

而且改一个硬链接文件所有硬链接文件都同时更新.

When we create hard links, we are actually creating additional name parts that all
refer to the same data part. The system assigns a chain of disk blocks to what is called an
inode, which is then associated with the name part. Each hard link therefore refers to a
specific inode containing the file's contents.

 3 是硬链接数目
 第一列是inode,硬连接的文件inode相同

 

 

 

• 参考资料:

The Linux® Command Line
William E. Shotts, Jr.
A LinuxCommand.

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