From 730a8d48d1f67a3772d6d276a8365039e921c108 Mon Sep 17 00:00:00 2001 From: Michael Kerrisk Date: Sat, 24 Oct 2020 12:54:11 +0200 Subject: [PATCH] signal.7: Add reference to seccomp_unotify(2) The seccomp user-space notification feature can cause changes in the semantics of SA_RESTART with respect to system calls that would never normally be restarted. Point the reader to the page that provide further details. Signed-off-by: Michael Kerrisk --- man7/signal.7 | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/man7/signal.7 b/man7/signal.7 index 29c160fa2..bc3155605 100644 --- a/man7/signal.7 +++ b/man7/signal.7 @@ -857,6 +857,15 @@ The .BR sleep (3) function is also never restarted if interrupted by a handler, but gives a success return: the number of seconds remaining to sleep. +.PP +In certain circumstances, the +.BR seccomp (2) +user-space notification feature can lead to restarting of system calls +that would otherwise never be restarted by +.BR SA_RESTART ; +for details, see +.BR seccomp_unotify (2). +.\" .SS Interruption of system calls and library functions by stop signals On Linux, even in the absence of signal handlers, certain blocking interfaces can fail with the error