From 18777d00085732d47f00bf61b3dbee1cc62d7fbb Mon Sep 17 00:00:00 2001
From: ngie <ngie@FreeBSD.org>
Date: Tue, 12 Feb 2019 02:57:34 +0000
Subject: [PATCH] MFC r339343,r343444:

r339343 (by allanjude):

Document that sendfile(2) can return ENOTCAPABLE

PR:		232207

r343444:

Document that `sendfile` will return an invalid value for `sbytes` if provided an invalid address

This is meant to clarify the fact that the system call will not fail
with -1/EFAULT, as one might expect, when reading the sendfile(2)
manpage today.

While here, pet the mandoc linter, when dealing with the section that
describes valid values for `flags`.

PR:		232210
Approved by:	jtl (mentor)
Differential Revision: https://reviews.freebsd.org/D19150
---
 lib/libc/sys/sendfile.2 | 21 +++++++++++++++++++--
 1 file changed, 19 insertions(+), 2 deletions(-)

diff --git a/lib/libc/sys/sendfile.2 b/lib/libc/sys/sendfile.2
index 9d5499cbf76..2119c4253d9 100644
--- a/lib/libc/sys/sendfile.2
+++ b/lib/libc/sys/sendfile.2
@@ -25,7 +25,7 @@
 .\"
 .\" $FreeBSD$
 .\"
-.Dd January 7, 2016
+.Dd January 25, 2019
 .Dt SENDFILE 2
 .Os
 .Sh NAME
@@ -104,7 +104,7 @@ variable pointed to by
 The least significant 16 bits of
 .Fa flags
 argument is a bitmap of these values:
-.Bl -tag -offset indent
+.Bl -tag -offset indent -width "SF_USER_READAHEAD"
 .It Dv SF_NODISKIO
 This flag causes
 .Nm
@@ -314,6 +314,12 @@ is negative.
 .It Bq Er EIO
 An error occurred while reading from
 .Fa fd .
+.It Bq Er ENOTCAPABLE
+The
+.Fa fd
+or the
+.Fa s
+argument has insufficient rights.
 .It Bq Er ENOBUFS
 The system was unable to allocate an internal buffer.
 .It Bq Er ENOTCONN
@@ -375,3 +381,14 @@ The
 .Fx 11
 implementation was written by
 .An Gleb Smirnoff Aq Mt glebius@FreeBSD.org .
+.Sh BUGS
+The
+.Fn sendfile
+system call will not fail, i.e., return
+.Dv -1
+and set
+.Va errno
+to
+.Er EFAULT ,
+if provided an invalid address for
+.Fa sbytes .
-- 
2.45.0