vertx / io.vertx.reactivex.core.dns / DnsClient / lookup4

# lookup4

`open fun lookup4(name: String, handler: Handler<AsyncResult<String>>): DnsClient`

Try to lookup the A (ipv4) record for the given name. The first found will be used.

### Parameters

`name` - the name to resolve

`handler` - the to notify with the io.vertx.reactivex.core.AsyncResult. The handler will get notified with the resolved java.net.Inet4Address if a record was found. If non was found it will get notifed with `null`. If an error accours it will get failed.

Return
a reference to this, so the API can be used fluently