POSIX message queues allow local processes to exchange data in the form
of messages. This API is distinct from that provided by System V
message queues, but provides similar functionality.
There is one backwards-incompatible API change:
POSIX_MQ#send returns +true+ on success instead of +nil+
for consistency with POSIX_MQ#trysend.
This release adds the POSIX_MQ#trysend, POSIX_MQ#tryreceive and
POSIX_MQ#tryshift interfaces to avoid exceptions on common
EAGAIN errors for users of non-blocking queues.
Bugfixes: non-blocking behavior changes to a shared descriptor
in a different process are reflected immediately in the child
(this won’t fix race conditions in your code, however).
Minor bugfixes for posix-mq-rb(1) and quieted warnings for