Creating directory hard links in Mac OS X [duplicate]

Question

How can I create a hard link to a directory in Mac OS X?

This feature has been added to their file system in Mac OS X v10.5 (Leopard) (for time machine), but I could not find any information on actually using it from the command line.

Answer 1

I have bundled up the suggested answer in a Git repository if anybody is interested: https://github.com/selkhateeb/hardlink

Once installed, create a hard link with:

hln source destination 

I also noticed that unlink command does not work on Mac OS X v10.6 (Snow Leopard), so I added an option to unlink:

hln -u destination 

---

To install Hardlink, use Homebrew and run:

brew install hardlink-osx 

Answer 2

Unfortunately Apple has crippled the ln command. You can use the following program to create a hard link to a directory:

#include <unistd.h> #include <stdio.h>  int main(int argc, char* argv[]) {  if (argc != 3) {   fprintf(stderr,"Use: hlink <src_dir> <target_dir>\n");   return 1;  }  int ret = link(argv[1],argv[2]);  if (ret != 0)   perror("link");  return ret; } 

Take into account that the hard linked directories may not be in the same parent directory, so you can do this:

$ gcc hlink.c -o hlink $ mkdir child1 $ mkdir parent $ ./hlink child1 parent/clone2