A unique identifier for an attached display.
- macOS 10.0+
- Mac Catalyst 13.0+
- Core Graphics
In Quartz, the term display refers to a graphics hardware system consisting of a framebuffer, a color correction (gamma) table, and possibly an attached monitor. If no monitor is attached, a display is characterized as offline.
When a monitor is attached, Quartz assigns a unique display identifier (ID). A display ID can persist across processes and typically remains constant until the machine is restarted.
When assigning a display ID, Quartz considers the following parameters:
Position in the I/O Kit registry
For information about how to obtain a display ID, see Finding Displays.