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Comment by icambron | Hacker News Reader

I suspect ln is at the top of the man list because no one can ever remember what order the arguments go in.

I could memorize it from the moment I realized that it works exactly like 'cp', i.e.

  cp <orig> <copy>

Hence I think of it as

  ln <orig> <link>

(edit: formatting)

Now, why isn't that in the ln man pages?

It is.

  SYNOPSIS
       ln [OPTION]... [-T] TARGET LINK_NAME   (1st form)

He just replaced TARGET with 'orig'

The confusion comes from understanding what the target of a link is. Of course, it's not the new file you're creating, it's the source. But if you were copying the file, then the target would be the destination.

Hence the confusion, I guess.

(I don't think I've ever read the ln man page. I learned it by trying it both ways until I learned which way was correct.)

I admit it's confusing, but I don't think it can be put much more succinctly than the man page makes it. The part where the name of the link itself is called "link name" really drives the point home.

I definitely refer to ln more than any other man page... Every time I use ln I say "target, link name" in my head.

OpenBSD always has great documentation: http://www.openbsd.org/cgi-bin/man.cgi?query=ln

  SYNOPSIS
     ln [-fhns] source [target]
     ln [-fs] source ... [directory]

Not to mention the detailed description as well as informative examples.

That is how I did it.

  ln -s target link

Easiest way to remember is that it's setup so that you can create multiple links to the same target. E.g.:

  ln -s /home/.bashrc {~user1,~user2,~user3}/.bashrc

That is a good way to remember it, and also a feature of ln I didn't know. Thanks

This is bash specific and may not work in your shell. (fish for example)

Works in zsh too, and you can tab auto-expand it to separate args if you like.

Sorry, the {} part was just so that the line wasn't too long (causing the scrollbar to show up).

i don't see what's impossible about parsing the arguments with target coming last, so i don't see how this works as a mnemonic

Indeed. For example, usermod (and many other tools) have the target as the last: usermod -aG group1,group2,group3 username

If you find it easier, you can just use the 'same as mv/cp' mnemonic mentioned elsewhere in this thread.

Another trick nobody else has mentioned is to remember that the 2nd argument is actually optional, so you can do things like:

    ln -s /path/to/some/file

And it'll create a symlink called "file" in the current directory. That wouldn't be possible if the arguments were the other way around.

The argument order mirrors the order of mv/cp (and the one-argument form gives a hint). I think people stumble upon the hard link/symlink issue.

cp has two interesting switches -s for symbolic links and -l for hard links. Plus it'll also link whole directory structures with -r. This might be a GNU only feature, I'm not sure.

I always remember that it is the opposite of Windows's mklink and then man it when I can't remember which way it is the opposite.

ln, as well as, cp and mv are all 'command source destination'

Yes, but the commands are normally interpreted differently in English. For example, 'cp A B' is copy from A to B that is, copying source A to destination B. But 'ln A B' could easily be interpreted as link A to B or make A a link to B where it is really making B a link to A. At least, that's why I sometimes forget the order.

I think this is because 'to copy' is a transitive verb and 'to link' is instransitive, in the sense they are used here...?

But with a quick perusal of the man page, you learn how the software works, and you don't have to make assumption based on interpretations of natural languages.

That and was it an upper case S or a lower case s?

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