From a1a3cae896d0c6f9ef62b2e647bdf388dcb80080 Mon Sep 17 00:00:00 2001
From: Michael Kerrisk <mtk.manpages@gmail.com>
Date: Fri, 21 Apr 2017 12:20:05 +0200
Subject: [PATCH] ioctl_ns.2: ERRORS: document ENOTTY

Signed-off-by: Michael Kerrisk <mtk.manpages@gmail.com>
---
 man2/ioctl_ns.2 | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/man2/ioctl_ns.2 b/man2/ioctl_ns.2
index 09a81c80a..0febd7a01 100644
--- a/man2/ioctl_ns.2
+++ b/man2/ioctl_ns.2
@@ -136,6 +136,16 @@ or
 in order to create a namespace.
 .SH CONFORMING TO
 Namespaces and the operations described on this page are a Linux-specific.
+.SH ERRORS
+Any of the above
+.BR ioctl ()
+operations can return the following errors:
+.TP
+.B ENOTTY
+.I fd
+does not refer to a
+.I /proc/[pid]/ns/*
+file.
 .SH EXAMPLE
 The example shown below uses the
 .BR ioctl (2)