Symbolic Links in Windows Using NTFS

In *nix systems, symbolic links are quite useful in linking files or directories. When using symbolic links, there exists only one physical location of the file or directory; this allows you to create several symbolic links all pointing to a single source. Here’s a couple of use cases for symbolic links:

  1. When I was building my Asterisk PBX using an old Buffalo TeraStation, I started to run out of firmware space on my /usr partition, which was located on the system’s flash memory. Having limited space, I needed to use some other storage to store the binaries. With the system being a NAS, the obvious solution was to use the RAID array. So, I compiled all the binaries onto the RAID array and created symbolic links in my /usr/bin directory.
  2. In my work environment, I had a set of common Javascript libraries and two distinct application types that used those libraries: desktop applications and phone applications. I had originally started developing phone applications first and so I mistakenly placed my common Javascript libraries in the phone applications folder. In this case, I simply created a symbolic link in my desktop applications folder that pointed to the phone applications’ Javascript libraries folder.

The symbolic link, whether a file or folder, behaves exactly like a file or folder. If you edit the file, you’re actually editing the physical file. If you cd into the symbolically linked folder, your directory structure remains intact; once you cd into the folder, it will follow the folder structure of the physical directory:

<...>\dashboard\apps\desktop\resources>mklink /D resources \inetpub\wwwroot\dashboard\apps\mobile\resources
<...>\dashboard\apps\desktop>cd resources

The ability to create symbolic links is not limited to *nix systems, however. You can create symbolic links in NTFS file systems by using the mklink command:

Creates a symbolic link.

MKLINK [[/D] | [/H] | [/J]] Link Target

        /D      Creates a directory symbolic link.  Default is a file
                symbolic link.
        /H      Creates a hard link instead of a symbolic link.
        /J      Creates a Directory Junction.
        Link    specifies the new symbolic link name.
        Target  specifies the path (relative or absolute) that the new link
                refers to.

As an example:

C:\inetpub\wwwroot>mklink /D resources c:\inetpub\wwwroot\somedirectory\resources
symbolic link created for resources <<===>> c:\inetpub\wwwroot\somedirectory\resources
C:\inetpub\wwwroot>cd resources
 Volume in drive C has no label.
 Volume Serial Number is XXXX-NNNN

 Directory of C:\inetpub\wwwroot\resources

02/08/2013  06:43 PM    <DIR>          .
02/08/2013  06:43 PM    <DIR>          ..
10/09/2012  05:08 PM    <DIR>          css
09/24/2012  04:53 PM    <DIR>          fonts
01/31/2013  12:13 PM    <DIR>          images
12/11/2012  03:04 PM    <DIR>          js
09/24/2012  04:49 PM    <DIR>          sass
02/08/2013  06:43 PM    <DIR>          sounds
07/09/2012  01:22 PM    <DIR>          svg
               0 File(s)              0 bytes
               9 Dir(s)  34,453,495,808 bytes free