Symbolic links

This section provides information on symbolic links.

General information

The system supports soft links in Cypress. This link is a node of type link referencing another target object.
The path to it is specified at link creation time. While the address is being computed for the operation, all attempts to access the link node are automatically redirected to the target object.

A link to a target object depends on its path.
If a target path is deleted or moved, the link will break. You will see a message similar to Link target does not exist.

A link node does not take up space on disk. Its resource_usage/disk_space attribute is equal to 0. Therefore, creating links cannot cause you to exceed your disk quota.
At the same time, each link is a node and uses up a single node; therefore, it is possible to exceed the nodes limit.

Creating

To create a symbolic link, use the link command. Use the address of the target node and the address of the link node in that order as arguments:

CLI

yt link //tmp/target_table //tmp/target_table_link

A link may reference arbitrary nodes and objects.
Such as the //tmp subtree in the home directory:

CLI

yt link //tmp //home/username/my_own_tmp

Redirects

Automatic redirects from a link node to a target object have a number of exceptions:

• The remove, create, and link commands for the target path are processed in the link node. When deleting //tmp/target_table_link, for example, a user will not damage //tmp/target_table.
• The move command will affect the target node invalidating the link node.

To disable redirection, add the & (ampersand) marker to the end of the link name.
This will help you explore the attributes of a link node, for example, rather than those of a target object.
Thus, to retrieve the target object path, run yt get //tmp/target_table_link&/@. You will get the path through the target_path attribute.

System attributes

In addition to attributes common to all nodes, link nodes also have the following properties: