toolchain/57001: sigevent(3) man page is outdated

[hopkinsza%gmail.com@localhost]

>Number:         57001
>Category:       toolchain
>Synopsis:       sigevent(3) man page is outdated
>Confidential:   no
>Severity:       non-critical
>Priority:       medium
>Responsible:    toolchain-manager
>State:          open
>Class:          doc-bug
>Submitter-Id:   net
>Arrival-Date:   Fri Sep 09 06:05:00 +0000 2022
>Originator:     Zach Hopkins
>Release:        9.3
>Organization:
n/a
>Environment:
NetBSD netbsdvm 9.3 NetBSD 9.3 (GENERIC) #0: Thu Aug 4 15:30:37 UTC 2022 mkrepro%mkrepro.NetBSD.org@localhost:/usr/src/sys/arch/amd64/compile/GENERIC amd64
>Description:
sigevent(3) man page says: "not yet fully functional in NetBSD: neither realtime signals nor SIGEV_THREAD are currently supported. Realtime functions that can generate realtime signals include... Expiration of per-process timers; see timer_create(2)."

I'm working on something that is currently using timer_create(2) to generate SIGUSR1 and SIGUSR2 on timer expiration and was a little sad to see that I would have to find a different solution to work on netbsd...

Except I tested it and it works! Noting Problem Report #42434 after a search, using SIGEV_SIGNAL, has worked (at least in some capacity / basic usage) since at least 2010. Not sure on the state of SIGEV_THREAD.
>How-To-Repeat:
n/a
>Fix:
Update sigevent(3) to document what is currently functional.