Create hard links

[cyberduck]

5ce7476 created the issue

Cyberduck has the ability to create symlinks, but if you need to have a large file in two or more different places, like movie files on a NAS server, where later you'd like to delete one of them, a hardlink is more useful. There are no FTP clients that I know of as of today that allows the creation of hardlinks, the alternative is to manually create them over SSH. However doing so in a client like Cyberduck would be much easier and faster.

[cyberduck]

@dkocher commented

10. sftp: Extension request "hardlink@openssh.com"

This request is for creating a hard link to a regular file. This
request is implemented as a SSH_FXP_EXTENDED request with the
following format:

	uint32		id
	string		"hardlink@openssh.com"
	string		oldpath
	string		newpath

On receiving this request the server will perform the operation
link(oldpath, newpath) and will respond with a SSH_FXP_STATUS message.
This extension is advertised in the SSH_FXP_VERSION hello with version
"1".

[cyberduck]

@dkocher commented

In 64eeb4466470035b16b45e35804013fc17b92e8f.

[cyberduck]

@dkocher commented

We are dependent on Bug 2227 in OpenSSH.