Windows 95 LPT driver (LPT.VXD) calls ACQUIRE_RESOURCE with ACQUIRE_STEAL. This service will steal ports owned by VMs, if stealing has been allowed by the user in Control Panel.
When LPT.VXD receives a RESOURCE_STEAL_REQUEST notification, it saves the state of the LPT or ECP port and returns TRUE. If the state cannot be saved at the current time, LPT.VXD returns FALSE.
After its port is stolen, LPT.VXD periodically attempts to steal back the port by calling STEAL_RESOURCE. This enables it to cooperate with periodic access by the VM for dongles, and so on.