Make Knot DNS listen/respond over stdin/stdout (in tests)
For testing (AFL and integrated (unit)tests), profiling (FDO, LTO, etc.) purposes, it would be great if Knot DNS could listen and respond over stdin/stdout, e.g.:
< packet_in knotd --stdio -c test.conf > packet_out
knotd would start, read config, read zones, parse packet on stdin, process it, write response to stdout and close itself.