On 14 Oct 2019, at 14:47, Lena--- via Exim-dev <exim-dev@???> wrote: > Or you can use
> ${if match{${run{/usr/local/bin/dig +short @... ...}}}{\N\.\N}}
Indeed, or one of many alternatives; unfortunately I could do without the execute overhead. Although our platform has a lot of compute resource available, using it to execute dig several tens-of-thousands to tens-of-millions of times a day isn't very efficient. Hence the readsocket idea - execute overhead is at startup time, everything else is connect->query->response.