src/lib/libc/sys/kqueue.2, branch release/11.1.0

MFC r320035:

2017-06-19T07:15:47+00:00

Move the description of kern.kq_calloutmax sysctl into a new paragraph
for better presentation.

Approved by:	re (delphij)

MFC r320034:

2017-06-19T06:48:21+00:00

Start a new sentence on the new line.

Approved by:	re (delphij)

MFC r306771:

2017-05-09T18:14:45+00:00

  Improve grammar.

Correct wording.

2016-05-03T15:58:35+00:00

Submitted by:	David A. Bright
MFC after:	2 weeks

Add EVFILT_VNODE open, read and close notifications.

2016-05-03T15:17:43+00:00

While there, order EVFILT_VNODE notes descriptions alphabetically.

Based on submission, and tested by:	Vladimir Kondratyev 
MFC after:	2 weeks

Issue NOTE_EXTEND when a directory entry is added to or removed from

2016-05-02T13:18:17+00:00

the monitored directory as the result of rename(2) operation.  The
renames staying in the directory are not reported.

Submitted by:	Vladimir Kondratyev 
MFC after:	2 weeks

As a reader service, explain NOTE_LINK reporting for the directories.

2016-05-01T20:54:29+00:00

Submitted by:	Vladimir Kondratyev 
MFC after:	1 week

Provide an example to the kqueue man page, showing

2016-05-01T18:09:34+00:00

a basic usage example.  Although it is an
untypical example for the use of kqueue, it is
better than nothing and should get people started.

PR:			196844
Submitted by:		fernando.apesteguia@gmail.com
Reviewed by:		kib
Approved by:		kib
MFC after:		5 days
Differential Revision:	https://reviews.freebsd.org/D6082

Make it possible to implement poll(2) on top of kqueue(2).

2015-08-05T07:34:29+00:00

It looks like EVFILT_READ and EVFILT_WRITE trigger under the same
conditions as poll()'s POLLRDNORM and POLLWRNORM as described by POSIX.
The only difference is that POLLRDNORM has to be triggered on regular
files unconditionally, whereas EVFILT_READ only triggers when not EOF.

Introduce a new flag, NOTE_FILE_POLL, that can be used to make
EVFILT_READ and EVFILT_WRITE behave identically to poll(). This flag
will be used by cloudlibc's poll() function.

Reviewed by:	jmg
Differential Revision:	https://reviews.freebsd.org/D3303

Make kevent(2) a cancellation point.

2015-03-29T19:14:41+00:00

Note that to cancel blocked kevent(2) call, changelist must be empty,
since we cannot cancel a call which already made changes to the
process state.  And in reverse, call which only makes changes to the
kqueue state, without waiting for an event, is not cancellable.  This
makes a natural usage model to migrate kqueue loop to support
cancellation, where existing single kevent(2) call must be split into
two: first uncancellable update of kqueue, then cancellable wait for
events.

Note that this is ABI-incompatible change, but it is believed that
there is no cancel-safe code that relies on kevent(2) not being a
cancellation point.  Option to preserve the ABI would be to keep
kevent(2) as is, but add new call with flags to specify cancellation
behaviour, which only value seems to add complications.

Suggested and reviewed by:	jilles
Sponsored by:	The FreeBSD Foundation
MFC after:	2 weeks