Function gio_2_0_sys::g_mount_guess_content_type

pub unsafe extern "C" fn g_mount_guess_content_type(
    mount: *mut GMount, 
    force_rescan: gboolean, 
    cancellable: *mut GCancellable, 
    callback: Option<GAsyncReadyCallback>, 
    user_data: gpointer
)