An ALSA node name minus its trailing PROFILE token — the profile-INDEPENDENT device identity
two profiles of the same card share. alsa_output.usb-RME_…-00.analog-stereo and
…-00.pro-output-0 both key to alsa_output.usb-RME_…-00.
The device part is matched GREEDILY so a card path carrying its own dots keeps them:
alsa_output.pci-0000_00_1f.3.analog-stereo → alsa_output.pci-0000_00_1f.3 (only the LAST
segment is the profile). undefined for anything that is not a profile-bearing ALSA node (an
app stream, the console's own node) — those have no profile to follow.
An ALSA node name minus its trailing PROFILE token — the profile-INDEPENDENT device identity two profiles of the same card share.
alsa_output.usb-RME_…-00.analog-stereoand…-00.pro-output-0both key toalsa_output.usb-RME_…-00.The device part is matched GREEDILY so a card path carrying its own dots keeps them:
alsa_output.pci-0000_00_1f.3.analog-stereo→alsa_output.pci-0000_00_1f.3(only the LAST segment is the profile).undefinedfor anything that is not a profile-bearing ALSA node (an app stream, the console's own node) — those have no profile to follow.