creating hard link to directory

[vickey_20]

I have found a way but it's not a lasting solution i.e only temporary ( unless given in the fstab)
We can use the "--bind" option of the mount command to mount directory onto some other directory thus providing all the data and making it accesible on the mounted one, but then it actaully won't be a hardlink coz the data deleted on the monted one will result in loss on the real directory.

[NNemec]

So, why do you want a hard link to a directory?

There is one use where it would be very valuable: incremental backups with rsync allow you to specify an older backup and use a hard link for any unchanged file. Has some very convenient results:
* a backup as plain directory tree from which individual files can be retrieved without need for special tools
* a complete directory tree for every backup
* no waste of disk space for unchanged files
* old versions of the backup can simply be deleted, freeing space for all files that don't exist in newer versions and leaving those intact that do

The only drawback is the cost of inodes for large, unchanged subtrees. Hard links do not cost disk space but they do cost inodes. Hard linking subtrees would be a nice solution for this.

However, I understand the problems with this:
* each directory could have multiple parents which would break a fundamental assumption in most codes
* if circular references are allowed, one would need to replace reference counting by garbage collection.
* to disallow circular references, one would need to detect them first. This would mean scanning a whole super-tree. Possible but costly...