Systemd USE flag transition and OpenRC script coexistence

Gentoo provides the systemd USE flag to enable integration across various packages. When this flag is active, Portage installs systemd service files, but many packages maintain their legacy OpenRC scripts simultaneously to ensure compatibility during the transition.

This dual-support mechanism creates a configuration boundary where both init systems may attempt to manage the same daemon. While the Gentoo Handbook outlines the migration path, the coexistence of service files in /etc/init.d and /usr/lib/systemd/system can lead to ambiguity regarding which init system holds primary authority over a specific process during the boot sequence.

Configuration Uncertainty

There is a lack of clarity on how the system should resolve conflicts when a package provides both service types but the global environment is in a partial migration state. Specifically, it is unclear if the presence of an OpenRC script should automatically suppress the systemd unit or vice versa.

• Does the system provide a deterministic priority mechanism to prevent duplicate service execution when both scripts exist?
• What is the recommended method to verify that a package is exclusively utilizing the systemd unit without manually auditing the filesystem?