Hmm works ok for me. What OS? 

Dne 16. 11. 2017 12:05 dop. napsal uživatel "kdevel via Digitalmars-d-learn" <digitalmars-d-learn@puremagic.com>:

On Wednesday, 15 November 2017 at 13:31:46 UTC, Daniel Kozak wrote:

This one works ok for me, but I am on linux: https://dpaste.dzfl.pl/f54decee45bc

It works, but it does not handle two connects in parallel. STR:

1. start the binary in console 1
2. telnet localhost 4444 in console 2
3. telnet localhost 4444 in console 3
4. enter a [RETURN] in console (3)

observed: nothing (the "thread" handling the first connect blocks)
expected: response

On my machine defaultPoolThreads() returns 1. This can easily be increased:

```
   defaultPoolThreads(8);
```

There is also another problem with Socket.select: It may return -1. This frequently happens when the ACCEPT socket is non-blocking and the select is interrupted (by the GC?) then errno == EINTR.

Also not having a timeout in the Socket.select of handle_socket allows for DOS attacks like the one above. In case of a timeout select also returns -1.