why is there no poll/select like mechanism for message queue?

Question

Like we can do, poll/epoll/select on an fd, we can not on msg queue id. I found some non standard methods to make msgqueue-id to fd, but afterall its a non standard. So my q

Answer 1

From the mq_overview man page:

Polling message queue descriptors

On Linux, a message queue descriptor is actually a file descriptor, and can be monitored using select(2), poll(2), or epoll(7). This is not portable.

So you can use poll and friends on message queues - just make sure you use the modern variant.