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frontmost_bundle_id

Function frontmost_bundle_id 

Source
pub fn frontmost_bundle_id() -> Option<String>
Expand description

Return an opaque string identifying the currently frontmost application.

On macOS this is the bundle identifier, e.g. "com.microsoft.VSCode". On Linux (X11 / XWayland) this is the WM_CLASS class component, e.g. "Code" or "Firefox". Pure Wayland windows (not running under XWayland) are not visible through this path and return None. On Windows this is the lower-cased executable path of the foreground process.

None when no app is frontmost, when reading fails, or on unsupported platforms. Costs one X11 round-trip on Linux, four objc_msgSends on macOS — well under a millisecond at the 1 Hz polling cadence in openlogi-gui::app_watcher.