Links command: ln
ln -s [original document] [destination file]
command English original intent: link
Description: Create link files
option: -s to create a soft link
Hard link feature:
1 have the same memory block and the i-node block, it can be seen as a same file
2. A node can be identified by the i
3. can not cross partitions
4. Can not use for directory
[the root @ localhost ~] # LS Anaconda-Binaries binaries.tar.gz the ks.cfg the ks.cfg Initial-Setup-test123 [the root @ localhost ~] # LN /root/anaconda-ks.cfg /tmp/ana.hard [ root @ localhost ~] # ls -i /root/anaconda-ks.cfg /tmp/ana.hard - i nodes of the two documents are identical 25165890 /root/anaconda-ks.cfg 25165890 /tmp/ana.hard
Soft link feature:
1. similar to Windows shortcuts
2. soft link has its own i-node block and block, but pieces of data stored in only the file name and i-node number of the original document, and not the actual file data
3. soft link permissions are 777, but the actual permissions need to look at the original file permissions
4. modify any file, other changes are
5. Delete the original file, soft links can not be used (original document must write the absolute path, otherwise the original and target files must be in the same directory)
[root@localhost ~]# ls anaconda-ks.cfg binaries binaries.tar.gz initial-setup-ks.cfg test123 test3 [root@localhost ~]# ln -s /root/test3 /tmp/test3.soft [root@localhost ~]# ln /root/test3 /tmp/test3.hard [root@localhost ~]# ll -i 总用量 20172 25165890 -rw-------. 2 root root 2165 5月 13 16:15 anaconda-ks.cfg 17070804 drwxr-xr-x. 14 501 games 175 6月 17 2017 binaries 25288936 -rw-r--r--. 1 root root 20647102 6月 22 2017 binaries.tar.gz 25165908 -rw-r--r--. 1 root root 2213 5月 13 16:17 initial-setup-ks.cfg 8546987 drwxr-xr-x. 3 root root 19 6月 15 16:59 test123 25708548 -rw-r--r--. 2 root root 0 6月 16 11:15 test3 [root@localhost ~]# ll -i /tmp/ 总用量 256 17070621 -rw-------. 1 root root 2165 6月 15 16:22 ana 17071146 -rw-------. 1 root root 2165 5月 13 16:15 anaconda-ks.cfg 25165890 -rw-------. 2 root root 2165 5月 13 16:15 ana.hard 25521547 drwxr-xr-x. 3 root root 19 6月 15 16:25 test1 8388685 drwxr-xr-x. 3 root root 19 6月 15 16:24 test3 25708548 -rw-r--r--. 2 root root 0 6月 16 11:15 test3.hard 17071129 lrwxrwxrwx. 1 root root 11 6月 16 11:16 test3.soft -> /root/test3
[root@localhost ~]# echo 111 >> /root/test3 [root@localhost ~]# cat /tmp/test3.soft 111 [root@localhost ~]# cat /tmp/test3.hard 111 [root@localhost ~]# echo 2222 >> /tmp/test3.soft [root@localhost ~]# cat /tmp/test3.hard 111 2222 [root@localhost ~]# cat /root/test3 111 2222 [root@localhost ~]# echo 3333 >> /tmp/test3.hard [root@localhost ~]# cat /root/test3 111 2222 3333 [root@localhost ~]# cat /tmp/test3.soft 111 2222 3333 [root@localhost ~]# rm -rf /root/test3 [root@localhost ~]# cat /tmp/test3.hard 111 2222 3333 [root @ localhost ~] # /tmp/test3.soft CAT CAT: /tmp/test3.soft: No such file or directory