Storing commands in OS socket buffers caused whole lot of
problems when free space in the buffer ran out. This patch
stores commands in ypipes instead and uses socketpair just
to signal the other thread, ie. at most one byte is stored
in the socketpair at any single instant.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

So far, the pipe termination code was spread among socket type
classes, fair queuer, load balancer, etc. This patch moves
all the associated logic to a single place.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Pieter Hintjens <ph@imatix.com>

As a side effect, broker HWM test was fixed.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

So far these were declared as C++ static functions which
was incorrect and caused warnings with SunStudio.
Signed-off-by: Martin Sustrik <sustrik@250bpm.com>

Signed-off-by: Martin Sustrik <sustrik@250bpm.com>