Talk:Symbolic link

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[edit] No Eleete Language

please use simple language to describe the problem. there is no need to use many foreign words. wikipedia aims to be understood by everyone not just a 'choosen few'. it would be perfect if you would use no technical english even for tech articles.

--212.202.37.226 17:10, 5 Jun 2005 (UTC)jan girke

[edit] Vista and symlinks

On another note, It seems that vista does not have true support for symlinks: http://slashdot.org/articles/06/11/19/018256.shtml Perhaps this should be corrected in the article.

You're right: Vista does not have 'true support for symlinks'. Vista can't even connect to a native Unix file system at all!
What Vista has is support for Symbolic Links, implemented as a component of NTFS. Sadly, Unix systems which connect to NTFS file systems don't have true support for NTFS Symbolic Links, because they don't understand the symbols.
Yes Symbolic Links are a component of NTFS. Yes, you have to load all of the current version of NTFS to get this feature. Yes, the NTFS Symbolic Link components only come with Vista. No, you don't need a new version of NTFS: NTFS allows you to add features.
And finally, Yes these symbolic links allow you to have different file and user permissions for each symbolic link. Nifty feature, yes?
Note: Windows 2000 had Windows SFU, which had NFS and symlinks 218.214.18.240 (talk) 06:02, 24 November 2007 (UTC)

[edit] Clean-up

The following sections have been removed:

Symbolic links can be remapped to allow locations of files to be addressed in a consistent manner, even though the physical location of the file may vary.

I don't think this is true. Symbolic links are immutable (they cannot be changed), however they can be removed and then a new symbolic link can be created in their place.

Using the 'ls -l' command, which is standard on these systems, a symbolically linked file might look something like this:
lrwxrwxrwx    1 jbailey  users         4 2003-02-07 16:49 link -> file
The 'l' in the first column is a hint that this file is a symbolic link. The information at the furthest right indicates that this file is called 'link', and that when you access it, you will see the contents of 'file'.

This doesn't belong in this article.

Symbolic links to directories can be dangerous for unaware programs working with directory trees. At best they can cause endless looping as well as pathname buffer overflows leading to crashes or dangerous malfunctions. At worst, deleting a directory tree will lead to the content of the symlinked directories being deleted as well. Unix tries to protect against this behavior to some extent by disallowing to destroy a directory symlink using the remove-directory (rmdir) system call, hence symlink-unaware programs will generally fail after trying to delete the first such link.

This may be a valid point, but I question its pertinence. At the very least, it should be reworded. Unix-like systems take no such precaution: 'rmdir' operates on the directory entry and ignores its contents. Directory trees cannot usually be deleted in a single action, either. A program must recurse through the tree, deleting all of the files in a directory, then removing the directory itself.—Kbolino 01:55, 7 January 2006 (UTC)

[edit] Windows supporting Symbolic Links

I just learnt that Windows 2000 (and above) does support symbolic links but is not well-documented. I was researching a problem with missing files and read this article - http://shell-shocked.org/article.php?id=284 - which is fairly descriptive about how Windows works with Symbolic links. gv —The preceding unsigned comment was added by Guhanv (talk • contribs) 12:34, 26 April 2007 (UTC).

No, Windows 2000 does not support symbolic links (except as shortcuts and mount points). NTFS 3, which is the default file system of Windows 2000, provides generic support for symbolic links, but Windows 2000 has no way to create or follow them. As the reference points out, you can use shortcuts or mount points "like" symbolic links. Or you can add support for symbolic links to Windows 2000, because Windows 2000 uses an extensible file system and an extensible command shell. But the same was also true of DOS 3.1 (david) 218.214.18.240 11:10, 10 June 2007 (UTC)
Actually, Windows 2000 does support symlink-type functionality, but for directories only, not files; see NTFS Junction point. Windows Vista implements proper symbolic links for all types of file, including across network shares; see NTFS symbolic link. All this is now in the article. And no, the same was not "true for DOS 3.1" (assuming you mean WIndows 3.1, which used DOS 6 or thereabouts): this functionality is all implemented using NTFS reparse points, of which FAT had no equivalent; WIndows 3.1 did not support NTFS. -- simxp (talk) 18:24, 3 May 2008 (UTC)

[edit] Similar Concepts

The link to "binding" is broken

[edit] Windows, Symlinks & killing the dead horse

Windows does NOT support symlinks. Symlinks is defined below the OS layer and is part of the file system and is NOT a type of file. Please stop comparing shortcuts to Symlinks. Lets also stop trying to predict what will be in future shaky releases of Windows as their track record is not good.

I will correct the main article, as less time should be devoted to OSes that do NOT suppport symlinks. --Kibbled bits 21:16, 18 June 2007 (UTC)

So can we expect to see a new article from you, titled "symlinks"?
This article is titled Symbolic Links, not symlinks. Windows Vista does support Symbolic Links, as well as Hard Links. NTFS is an extensible file system, and supports Symbolic Links when the necessary components are in place, as they are in Windows Vista.
Furthermore, Windows Explorer has always supported Symbolic Links, which are shortcuts, which are not symlinks. Windows Explorer is a command shell, so only command shell extensions (or environments like uwin) are able to use the command shell Symbolic Links. Windows Vista introduces a Symbolic Link implemented as part of the file system, so that any file system client is able to use the Symbolic Link.
Also, the new text is poor: even if it was correct, the focus is on what Windows cannot do, rather than on Symbolic Links 150.101.166.15 06:31, 4 July 2007 (UTC)
So just to be absolutely clear, what do you mean by "any file system client is able to use..."? What I want to know is, if I use this vista symbolic link, will every single program, no matter how old or poorly written or what circumstances it is running under, see that symbolic link as whatever it's linking to, or not? —Preceding unsigned comment added by 76.10.140.61 (talk) 19:46, 11 April 2008 (UTC)
With Vista's symbolic links, yes. With NTFS Junction points, yes. With NTFS Hard links, yes. With Windows Shortcuts, no. Clear? -- simxp (talk) 10:22, 3 May 2008 (UTC)

Can someone knowledgeable create a comparison of Windows shortcuts to symbolic links? Functionally for me at least there is no difference since they just get me to a long filename from a shorter filename on the desktop (and also start menu in windows) without typing forever or clicking through nested folders. 129.31.71.161 09:37, 2 August 2007 (UTC)

Sigh. Junctions are *one implementation* of soft-links, that only work for directories. I believe they were actually (at least partially) a side effect of code for the Object Manager component (which gives access to every device, global mutex, file, registry entry, etc...) implemented for Terminal Services (remote login). Shortcuts are just files that Explorer and the ShellExecute() function interpret. Vista added *real* soft and hard links to NTFS (not the object manager), added mklink, and taught all their file programs about them (including Explorer). —Preceding unsigned comment added by 124.197.41.54 (talk) 02:33, 8 November 2007 (UTC)
Note, a form of junction (JOIN) existed even in DOS... Hard links were already in NTFS, for POSIX; Vista added management capability...Shortcuts are slow soft links, but there is no OS or FS support for programs (environments like uwin have to build their own support)...Functionally Windows shortcuts are the same as symbolic links to a user, but not to a user program...the distinction is important to anyone who uses a program (even Word or Excel) in Windows...Windows SFU supported symbolic links on NFS file systems...218.214.18.240 (talk) 05:55, 24 November 2007 (UTC)

[edit] Doctors?

"The misuse of soft links can be a cause extreme irritation in many subjects. Doctors report a significant increase in blood pressure, body temperature, and elevated vocal ranges. Persons with a history of heart conditions should refrain from the use of softlinks without first consulting with their physician."

What does this have to do with softlinks? —Preceding unsigned comment added by 68.197.165.133 (talk) 06:55, 15 September 2007 (UTC)

[edit] White Knight Through the Looking Glass

So can anyone decisively explain the differences between filenames, shortcuts, hard and symbolic links, and the data they represent? —Nahum Reduta 05:10, 2 December 2007 (UTC)