Function cef_get_exit_code 

pub unsafe extern "C" fn cef_get_exit_code() -> c_int

This function can optionally be called on the main application thread after CefInitialize to retrieve the initialization exit code. When CefInitialize returns true (1) the exit code will be 0 (CEF_RESULT_CODE_NORMAL_EXIT). Otherwise, see cef_resultcode_t for possible exit code values including browser process initialization errors and normal early exit conditions (such as CEF_RESULT_CODE_NORMAL_EXIT_PROCESS_NOTIFIED for process singleton relaunch behavior).