Wakeable poll

[royreznik]

Description

When i poll a message, if there is no message, i can not terminate the process.
Would it be intersting to wrap the polling with wakeable poll?

like wraping this function:

rkm = rd_kafka_consumer_poll(self->rk, cfl_timeout_ms(tmout));

inside a while start_time + timeout > current_time statement, and put a little timout inside,
so it will be wakeable?

Interesting for a PR?

[edenhill]

We want to address this problem in librdkafka, allowing all blocking calls to be cancelled, something we'll look into later this year.