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Simlinks
A symlink is a soft or hard link to a directory location to another directory location or file. I am only interested in the soft link. It effectivily allows a directory tree to be made for different non-structured directory locations, even across partitions.
Simple use is: ln -s "path/directory or file" "path/symlink name", where option -s is to create a symlink. See ln –help or man ln for more information.
- To remove symlink
rm "path/symlink name" - To list symlink
ls "path/symlink name" - To list symlink directory contents
ls "path/symlink name/" - Use
-fflag to force - Use
-sflag for soft link, default is hard link
| Comparison Parameters | Hard link | Soft link |
|---|---|---|
| Inode number* | Files that are hard linked take the same inode number | Files that are soft linked take a different inode number |
| Directories | Hard links are not allowed for directories* | Soft links can be used for linking directories |
| File system | It cannot be used across file systems | It can be used across file systems |
| Data | Data present in the original file will still be available in the hard links | Soft links only point to the file name, it does not retain data of the file |
| Original file’s deletion | If the original file is removed, the link will still work as it accesses the data the original was having access to. | If the original file is removed, the link will not work as it doesn’t access the original file’s data. |
| Speed | Hard links are comparatively faster | Soft links are comparatively slower |
Notes:
- Inode number – Index node number is a unique number assigned to all files in a Linux/Unix system.
- Hard links on directories can cause fundamental problems. Original Unix command had flags to allow (
-dand-F), however most modern operating systems do not allow hard links on directories.
Soft symlink ownership is not particularly important as it has full permissions (777) and file access is determined by real file permissions.
References
- Linux Soft and Hard Link Guide (10 ln Command Examples)