lock type window_id [window_id...]
A string identifying the type of the lock. Currently only " view " is supported.
The identifier of the window to lock.
The lock command allows windows to be locked together so that when one updates, all other locked windows update with it.
Currently, only a window's view may be locked.
A list of locked windows for each type is kept. As windows are locked using the lock command, they are added to the list of locked windows. Windows can be removed from this list using the unlock command.
When a window is added to the list of locked windows, the shared attributes of the already-locked window are copied to the new window. In this way, a window may be "locked-to" an existing set of attributes.
When the attributes of one window in the list change, these changed attributes are copied to all of the windows in the list, causing the "lock" behavior.