Is there a way to edit a symlink without deleting it first? [duplicate]

Answer 1

As others have mentioned, you basically have to delete the symlink first, either manually or by passing the -f flag to the ln utility.

Years ago, I had to make small edits to symlinks pretty frequently, so I wrote a simple readline-based utility (edln) to make this less annoying. In case anyone else finds it useful, I've put it online at https://github.com/jjlin/edln/.

edln will display the original symlink target; you can then use the arrow keys, or standard readline keystrokes (M-b, M-f, C-d, etc.) to move around and edit the target.

Answer 2

Just googled, found no good answer and had to solve myself:

ln -f -s -T `readlink SomeLibrary | sed 's/version.old/version.new/'` SomeLibrary

Editing by definition means not recreating from scratch but changing partly. Any answer requiring to memorize a path, maybe long or with weird symbols, is definitely bad.

Answer 3

On OSX, the man page for ln says you can do it like this

ln -shf /location/to/link link name

From the man page:

The options are as follows:

 -F    If the target file already exists and is a directory, then remove it so that the link may occur.  The -F
       option should be used with either -f or -i options.  If none is specified, -f is implied.  The -F option is
       a no-op unless -s option is specified.

 -h    If the target_file or target_dir is a symbolic link, do not follow it.  This is most useful with the -f
       option, to replace a symlink which may point to a directory.

 -f    If the target file already exists, then unlink it so that the link may occur.  (The -f option overrides any
       previous -i options.)

 -i    Cause ln to write a prompt to standard error if the target file exists.  If the response from the standard
       input begins with the character `y' or `Y', then unlink the target file so that the link may occur.  Other-
       wise, do not attempt the link.  (The -i option overrides any previous -f options.)

 -n    Same as -h, for compatibility with other ln implementations.

 -s    Create a symbolic link.

 -v    Cause ln to be verbose, showing files as they are processed.

Answer 4

No. The symlink system call will return EEXIST if newpath already exists. You can only link from a new node in the filesystem. What's the requirement here? If you're worried about a race due to the non-atomicity of the unlink/symlink calls, then you might want to rethink the architecture a little to provide synchronization elsewhere. There have been some scary security bugs introduced by this kind of thing.