epoll_ctl.2: Document EPOLLWAKEUP

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>

diff --git a/man2/epoll_ctl.2 b/man2/epoll_ctl.2
index 1fbe74eeea4ed656bc1247263fa7d3ab7a4fa47f..6388f19195f116d01aa98b4b21fedff17eaf8ef1 100644 (file)
--- a/man2/epoll_ctl.2
+++ b/man2/epoll_ctl.2
@@ -154,6 +154,26 @@ The user must call
 with
 .B EPOLL_CTL_MOD
 to rearm the file descriptor with a new event mask.
+.TP
+.BR EPOLLWAKEUP " (since Linux 3.5)"
+If
+.B EPOLLONESHOT
+and
+.B EPOLLET
+are clear and the process has the
+.B CAP_BLOCK_SUSPEND
+.BR capability (7),
+ensure that the system does not enter "suspend" or
+"hibernate" while this event is pending or being processed.
+The event is considered as being "processed" from when it returned by
+a call to
+.BR epoll_wait (2)
+until the next call to
+.BR epoll_wait (2)
+on the same
+.BR epoll (7)
+file descriptor.
+.\" commit 4d7e30d98939a0340022ccd49325a3d70f7e0238
 .SH RETURN VALUE
 When successful,
 .BR epoll_ctl ()