The pipelinefs filesystem mount point.

Local name of compute node pipeline instance.

Pipeline flow control; equivalent to WCBE_FLOW_MSG message. The values that can read from or written to this file, together with their WCBE_FLOW_MSG value equivalents are

Pipeline instance (remote) name; equivalent to WCBE_NAME_MSG message. This is a read-only file because the (remote) instance name may not be changed.

Pipeline lag frame source; equivalent to WCBE_SRC_MSG message. This file's content is the URI of the pipeline's lag frame source.

“Live” timestamp flag; equivalent to WCBE_LIVE_TS_MSG message. This file only exists if the pipeline's lag frame source is a BLF file. The strings “true” and “false” are the only valid strings for this file's content.

Frame playback rate; equivalent to WCBE_RATE_MSG message. This file only exists if the pipeline's lag frame source is a BLF file. The file's content is a string representation of the frame playback rate in frames per second.

Symbolic link to directory for the active configuration (under configurations directory). This symbolic link only exists when one of the pipeline's configurations is in the “active” state.

The directory containing the pipeline's configurations.

The pending configurations actions for the pipeline. This is a read-only file, which exists only when there are pending configuration actions. Each line of the file's contents is a string comprising a configuration action and a configuration name (or action target). The pending actions are listed in the order in which the actions were created. The valid configuration actions are in the following list: “create”, “activate”, and “destroy”.

Local configuration name.

Pipeline status. This file's content is either a list of pending configuration actions to be applied to the configuration, or the current configuration status. The valid pending configuration actions are in the following list: “pending-create”, “pending-activate”, and “pending-destroy”. The valid configuration status values are “active”, “inactive”, “active-retired”, and “inactive-retired”. The only valid string that may be written to this file is “activate” (but one should not expect to read back the same value).

The directory containing the configuration's GStreamer pipelines.

The pipeline names under this directory are given by the names specified in the configuration. However, one pipeline, INPUT_STAGE, is never given explicitly by a configuration, and will only appear under one configuration of each compute node pipeline instance at any given time. The INPUT_STAGE pipeline corresponds, unsurprisingly, to the GStreamer pipeline in the input stage of each compute node pipeline.

GStreamer pipeline name.

GStreamer element name.

Directory containing the element's pads.

GStreamer pad name.

Value of pad's negotiated capabilities (read-only).

Pad's peer (read-only). The name of the peer is provided in the format

[element name]/[pad name]

where element name is the name of an element in the same pipeline as the current pad, and pad name is the name of a pad in the named element.

Directory containing the elements GStreamer properties.

Note that the values of all the element properties appearing in the pipelinefs filesystem are given in string representations. The actual property value types are provided through an extended attribute of each file in this directory.^[2] The name of the extended attribute used for the property type metadata is “user.edu.nrao.widar.gtype”; the values of this attribute are GType names.

Element property name