Subject: Re: poll(2)
To: Jason Thorpe <thorpej@nas.nasa.gov>
From: Jonathan Stone <jonathan@DSG.Stanford.EDU>
List: tech-kern
Date: 12/09/1996 17:09:57
>Just wanted to get tech-kern@netbsd.org on this thread, too :-)
>
>"Discuss." :-)

Uh, well, then....

AFAIK, there aren't yet any NetBSD ports with significantly
better than millisecond time-of-day-clock (and thus forced process-
scheduling) resolution.  So milliseconds are currently as good as
you'll get.

You can add a syscall specifying a nanosecond interval, but anyone
thinking they're going to get _nano_second-level wakeups is,
currently, deluding themselves.  (I still get ~4usec syscall times on
a 200MHz P6.)

Clearly we should add a nano-second resolution poll interface.
Once we do so, regardless of the actualy in-kernel resolution,
poll(2) and upoll(3) become poll(3) and upoll(3).

Re naming, npoll() is more consistent with the sleep()/usleep() usage.
Does POSIX have anything to say here?

If we did this _now_ we could, perhaps, reuse the existing syscall
number,  since AFAIK poll(2) has never been in an official NetBSD release.