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Integration / D Bus Interview Questions

Describe a D-Bus unique connection name?

A unique connection name is the identifier the bus daemon automatically assigns to every connection the moment it connects, in a format like :1.42, starting with a colon to distinguish it from well-known names.

Unlike a well-known name, which a service must explicitly request and which can be released, transferred, or contested, the unique name is assigned once per connection, never changes for the lifetime of that connection, and is guaranteed unique across the bus. It's effectively the true, low-level identity of a connection, while well-known names are more like human-friendly aliases pointing at whichever connection currently owns them.

Tools like dbus-monitor often show unique names in message headers as the actual sender, even when the human-readable well-known name is what a developer typically targets in code.

A D-Bus unique connection name typically looks like:
Compared to a well-known name, a unique connection name:

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