FAST: Use non-blocking reads for RX
FAST: Use non-blocking reads for RX

xread function blocks the caller even if the underlying
file descriptor associated with the buffer is a non-blocking.
This patch makes FAST receving engine be able to handle
non-blocing file descriptors.

Signed-off-by: Marat Stanichenko <146c4a279a7427b2cc19a19b6130cbb7ee404ab1@gmail.com>
Signed-off-by: Pekka Enberg <add4fcd06328a394f0ad91feda7ee057316dc5ed@kernel.org>

etoestja/libtrading,femtotrader/libtrading,NunoEdgarGub1/libtrading,jvirtanen/libtrading,Bitcoinsulting/libtrading,NunoEdgarGub1/libtrading,Bitcoinsulting/libtrading,fengzhyuan/libtrading,svdev/libtrading,divaykin/libtrading,divaykin/libtrading,fengzhyuan/libtrading,mstanichenko/libtrading,jvirtanen/libtrading,svdev/libtrading,femtotrader/libtrading,mstanichenko/libtrading,libtrading/libtrading,penberg/libtrading,etoestja/libtrading,penberg/libtrading,libtrading/libtrading