Function ostree_sys::ostree_kernel_args_append_proc_cmdline

pub unsafe extern "C" fn ostree_kernel_args_append_proc_cmdline(
    kargs: *mut OstreeKernelArgs, 
    cancellable: *mut GCancellable, 
    error: *mut *mut GError
) -> gboolean

This is supported on crate feature v2019_3 only.