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The Fifowatcher module manages the fifo pipes (i.e., the vsys entries) that are made available to users as access points to vsys. There are currently two types of fifo watchers: standard fifo watchers, and direct fifo watchers. Standard fifo watchers act as proxies between the client and the corresponding vsys script. When the client dies, the intermediate fifo watcher may or may not close the connection to the vsys script depending on its type. If the script is persistent, then the connection will be kept open, and re-activated on subsequent requests from slices. Direct fifo watchers create a splice between the client and the script at the backend and have the advantage of being faster.