How to use the command pw-cli (with examples)

The pw-cli command is the PipeWire Command Line Interface, which provides a way for users to interact with PipeWire, a server and API for handling multimedia applications. PipeWire is designed to be a replacement for PulseAudio, JACK, and other similar audio and video servers.

Use case 1: Print all nodes (sinks and sources) along with their IDs

Code:

pw-cli list-objects Node

Motivation: This command allows users to list all the available audio and video nodes (sinks and sources) in the PipeWire server along with their corresponding IDs. This can be useful for debugging purposes or when trying to identify specific nodes for configuration or routing.

Explanation:

• pw-cli - The command line interface for interacting with PipeWire.
• list-objects - Command to list all objects of a specific type.
• Node - Specifies the type of object to list, in this case, “Node” which represents audio and video nodes.

Example output:

Node 4
Node 5
Node 6
Node 7
...

Use case 2: Print information about an object with a specific ID

Code:

pw-cli info 4

Motivation: This command allows users to retrieve detailed information about a specific node or PipeWire object using its ID. This can be helpful to understand the properties and capabilities of a node, or when troubleshooting issues related to a particular object.

Explanation:

• pw-cli - The command line interface for interacting with PipeWire.
• info - Command to retrieve information about a specific object.
• 4 - The ID of the object to retrieve information for.

Example output:

Object type: node
Node ID: 4
Name: System Playback
Type: PipeWire:Unknown
State: RUNNING
...

Use case 3: Print all objects’ information

Code:

pw-cli info all

Motivation: This command provides a way to display detailed information about all the objects available in the PipeWire server. It can be useful for understanding the current state of the server, identifying issues, or gathering diagnostic information.

Explanation:

• pw-cli - The command line interface for interacting with PipeWire.
• info - Command to retrieve information about objects.
• all - Specifies to retrieve information about all available objects.

Example output:

Object type: core
Core ID: 1
Name: core
Type: PipeWire:Remote
State: RUNNING

Object type: node
Node ID: 4
Name: System Playback
Type: PipeWire:Unknown
State: RUNNING

Object type: node
Node ID: 5
Name: System Capture
Type: PipeWire:Unknown
State: RUNNING

...

Conclusion:

The pw-cli command line interface provides a convenient way to interact with the PipeWire server, allowing users to list objects, retrieve information about specific objects, and obtain information about all available objects. These use cases can be helpful for understanding the current state of the server, troubleshooting issues, or configuring nodes and routing within the multimedia framework.