C API Changes for Release 0.9.6

SONAME control

SONAME versioning has been enabled for libddcutil. To differentiate the lastest library from all prior libraries, the current version is 1.0.0, i.e. libddcutil.so.1.0.0.

New Functions

New Functions Comment
ddca_enable_usb_display_detection   Control whether USB display detection is enabled
ddca_is_usb_display_detection_enabled   Indicates if USB display detection is enabled

Notes on ddca_enable_display_detection():

  • Must be called before any function call that triggers display detection.
  • Returns DDCRC_INVALID_OPERATION. if display detection has already occurred.
  • Returns DDCRC_UNIMPLEMENTED if ddcutil was built without USB support.
  • This setting is global to all threads.

Changed functions


No longer returns DDCRC_ARG to indicate that the VCP version was unqueried, as this error is no longer possible. DDCRC_ARG now always indicates an invalid display reference.


New status code DDCRC_ALREADY_OPEN indicates that the display is already open in the current thread. (As before, DDCRC_LOCKED indicates the display is open in another thread.)

Sample Program Changes

Fix the cause of a failure in demo_feature_list.c.