Loopback

The Loopback node-type loops back every sample which has been sent to it. Internally it is implemented by a FIFO queue.

It can be used to chain multiple paths together by using the same Loopback node as an output node in the first path and as a source in the second path.

Prerequisites

This node-type does not have any special library dependencies. It is always available.

Implementation

The source code of the node-type is available here: https://git.rwth-aachen.de/acs/public/villas/node/blob/master/lib/nodes/loopback.cpp

Configuration

queuelen (integer)

The queue length of the internal queue which buffers the samples.

samplelen (integer)

The number of values each buffered sample can store.

mode (string: "pthread" | "polling" | "pipe" | "eventfd" | "auto") = "auto"

Specify the synchronization mode of the internal queue.

Example

nodes = {
        loopback_node = {
                type = "loopback",                      # A loopback node will receive exactly the same data which has been sent to it.
                                                        # The internal implementation is based on queue.
                queuelen = 1024,                        # The queue length of the internal queue which buffers the samples.
                mode = "polling"                        # Use busy polling for synchronization of the read and write side of the queue
        }
}