Shared Library Changes for Release 2.2.2

Shared library libddcutil is backwardly compatible with the ones in ddcutil 2.2.1 and 2.2.0. The SONAME is unchanged as libddcutil.so.5. The released library file is libddcutil.so.5.4.0.

Watch mode udev

New watch mode udev uses libudev to watch for display connection and disconnection. This is now the default watch mode if executing on Wayland and ddcutil was built to use libudev, which is normally the case (configure option --enable-udev). This change addresses issues raised in KDE-Plasma PowerDevil merge request 542.

Watch mode xevent remains the default if executing on X11 and ddcutil was built to use the X11 API, which is normall the case (configure option -enable-x11).

A specific watch mode can be forced by including option --watch-mode udev, --watch-mode xevent, or --watch-mode poll in the user's ddcutilrc configuration file.

There is presently no API function for selecting watch-mode. A client program can specify a watch-mode other than the default by including a --watch-mode option in the libopts parameter string passed to ddca_init2().

Fixed

• ddca_set_non_table_vcp_value() was not performing verification,
• ddca_display_ref_from_handle(): was not converting internal to external display reference, causing a segfault. Issue #528.